I have 16X10" bogart wheels with 6" backspacing & a 28X12.50 ET streets but it doesn't hook.I was wondering if 15x12" weld alumastars with 7" backspacing would fit a 70. Going to run a 325 M/T radial or 28X11.5 M/T slickwhich both have about a 13" section width.I have a stock width 9" rear.Don't want to do any more modification than cutting outer fender.Will they fit?Suggestions?Ideas?

I believe you'd have to modify the lower shock mount at a minimum.

That is not a problem the 9" has a shock mount that is farther inward.The backspacing sounds right?My setup now is close to the outside and has about 3/4" on the inside but that is without trimming.

If you only have 3/4" available on the inside, then you won't be able to go from a 6" bs to a 7" without hitting. 6 1/2" bs sounds like the most you could go. Being that you have 10" wide wheels on there now, if you go to 12" and can only increase the backspacing by a 1/2", the wider wheels will end up sticking out an 1 1/2" further than the current ones. That may be too much for a fender trim to help you with. Unless you cut more than just the lip.

I meant 3/4" from the tire which would be about an 1 3/4" from the wheel.So with 1" more backspacing that would leave 3/4". In theroy the tire shoud only buldge 1/2" on each side because it would be a 12" wheel and a 13" tire.Therefore leaving a 1/4" on the inside. This should also only add 1/2" to the outside overall because the wheel is 1" farther to the front but again only a 1/2" buldge.It calculates right I just wondered if anyone had done a tire this size in a stock fender?
Widetires22 what size tire do you have?

275/60-15 on a 10" wheel right now.

I have 16X10" bogart wheels with 6" backspacing & a 28X12.50 ET streets but it doesn't hook.I was wondering if 15x12" weld alumastars with 7" backspacing would fit a 70. Going to run a 325 M/T radial or 28X11.5 M/T slickwhich both have about a 13" section width.I have a stock width 9" rear.Don't want to do any more modification than cutting outer fender.Will they fit?Suggestions?Ideas?

15x10" will fit fine with the 325/50R15's. Its what I have currently on the 69'.

Got any pics of the 69?