I have been buying parts for cars for about 35 years now. Mostly corvettes, I have been doing body work for at least 30 years and have owned my own shop.
I have never come across such garbage that they sell for replacement panels. I put quarter skins on...twice, because I didn't like how the first pair looked. The second pair was so wavy you could go surfing down the side. It took me over 6 months to get them straight. I put new doors on the car and fought them the whole way. Now I am putting new fenders on the car. The contour of the fender didn't even come close to the doors. I notched the inside and got it very close. Then I couldn't get the door to fender gap right. So I welded an 1/8 rod to the front of the door. This caused some warping that I have pretty well straightened out. There is now more plastic on this car than if I had fixed the original rust.
At least with vettes if something was out of whack you put some glass on the car and did what you had to.
I bought all "new" sheetmetal for this car. Goodmark so I figured it was good quality. The deck lid and hood are glass so I figured that they would need work......they fit the best.

What crap................................... rant over.

As long as we are willing to purchase this garbage, they will continue to sell that sh%t.
I have tried to repair rather than buy that sh%t. I know thats not possible all the time.

I've ordered parts, and tossed them in the garbage when they arrived, and repaired the original, because it was less work

Yea same here bought 2 new fenders quarter panels skin and new door, 1 fender was ok not perfect but usable,the other total garbage didnt line up no matter what so had to rebuild old one same as the door, the door measure out over a half inch shorter than origanal and it will not line up at all aftermarket parts are all crap doesnt matter who is selling them 800.00 dollars in parts a guy can use that expensive for garage orniments joe 68 chevelle

I bought and installed two quarter panels that fit reasonably well. Sure seems to be a crap shoot on what your going to get. :(

I am doing a Hemi GTX right now qtrs. fit real nice but some waves down the side as could be.They were from AMD and there stuff is really nice, they are now working on GM parts and will put some of the A/M companies to shame. The 1970 Chevelle LS5 I just finished had a Goodmark LT door shell and you thought it was born with the car perfect ! The LT fender was from Goodmark and also lines and fit were really good, only problem was the front edge to the hood it was too low, I drilled out the 5 spot welds and it popped right into place I spot welded it back and finished, some is hit some is _hit. Good luck !!!!

Yeah, the same here, bought 2 new front fenders for my 66, the entire inner structure was welded in wrong, no way to make them work, I ended up using sheet metal as patch panels to repair my old ones. Forget about the deck lids, I bought 2, recieved 3, because the 1st one was heavily damaged in shipping, still fought one for weeks, and thought we had it right, until the weather got cold, then it started getting all kinds of waves in it. I gave away all of them, and found a decent used one to work with. My SS hood didn't give much problems though, must have got lucky on it. When I first started ordering parts for mine several years ago, I was still able to purchase a NOS quarter for the left side, but had to use an after market for the right side, but it worked out well, and I was pleased with it.

come to think of it, my quarter skins needed a nice skim coat to get straight, too

This thread makes me appreciate my 69SS project with all original sheetmetal!

yep the repop stuff is crap, i went through this with my 69 camaro. Im glad i only needed a fender and a trunk lid.:) I ended buying a used fender and trunk lid

i am doing my first restoration project with my 69 vert.when i am done there wont be one piece of the metal on that car i did not touch or repair.from reading threads here i have tried where ever i can to use original used sheet metal parts.i bought quarter panels with wheel wells off a coupe,had a pair of original fenders,a original SS hood and i will have to repair them all before installing them on my car.
with that said i have also used repo parts when needed because i could not find any good donor parts.i bought some goodmark floor pans that fit great.did they need work yes but when it was all welded up they lined up almost prefect.i also used dynacorn inner and outer rockers on the passenger side of the car and was ever happy on how they also fit and turned out.i still have to reskin both doors with repop door skins, so the jury is still out on them.so far though i am very happy and surprised with the after market stuff.maybe i got lucky but i still think what ever you use there will be some type of mobs needed to make it fit.
original or not. some will just need more work.here are some pictures of my after market floor pans installed.you be the judge

It's definately a crap shoot, many of the quarter skins are sized to actually fit over the originals-this was a common used car lot type patch job done and what they were originally designed for-it takes many hours to get these types usable for quality results. The fenders are often welded up wrong or too short or long etc... The doors are usually complete garbage, doorskins are usually usable but the lock holes are usually wrong or they are dimensionally a little off. Full quartes-some good and some bad. A 68 Z-28 just got new quarters, roof skin, outer wheelhouses, trunk drop offs, drip rails, & trunk and front floors in my shop and overall I am pleased with how it went together-gaps and countours were OK but there were some small differences from OEM. Original sheetmetal is always better but I still am glad the aftermarket is offering all these parts to save these old cars.

The thing that really irks me is that I had to put a lot of plastic on the car to get it straight. To line up body contours I had to put plastic. The fender to the door contour was off and like I said before it wasn.t perfect dead on. So out comes the plastic and a couple of skim coats later it's about an 1/8 inch of plastic to get it lined up. I sanded and it is almost perfect, but I don't like to put plastic on that thick.
As for the other side the contour of the fender is off, but the door to fender gap is dead on. I guess the passenger side door was made longer.
All in all with a lot of tweeking and plastic the car will be nice and straight. But for what we pay for these parts they should be better.

When I went to ---- to get my '66 front fenders they brought out fender after fender full of defects until I found two that were presentable without a lot of correction. I went through 11 fenders, and the remaining 9 (total inventory at the time) went by mail-order to customers who never would suspect that I had already unwrapped their fenders and rejected them.

Cool for ----- to let me do this, bummer for them sending stuff like the remainder off to unsuspecting customers.

Putting them on, left side ok, right side sort of ok, so long as to make them bolt up I was willing to lower the core support all the way to the frame, which means of course that the style-line along the side takes a nose-dive up front.
I would have to add metal to get the door-fender gap a the bottom to be acceptable (about 3/8ths to 1/2" gap at the bottom and closed up at the top).

I'm ok at aligning fenders and doors, etc, these were simply made wrong.

Oh... they are Dynacorns, and with all the problems, I'm happy enough to make them work, the general shape of the fenders are ok (save for the ridiculous door gap stuff), although I will not toss any of my original United Auto Workers American Made original Chevrolet steel. It would be foolish to do that.

Eric