I am going to cut out my rear quarter on a 66. what is the best way to remove it for a new skin. how do you remove it from the rocker panel. is that welded will a sawzall be best???? and how do you split the inner well from the outer to install new outer well????

Don't use a sawzall. Use a cutting wheel either electric or air, and use the thinnest cutting wheel you can find. the sawzall will push and pull the metal creating bad warping. Most of the other questions you talk about are held together with spot welds, but unless you have to replace the entire outter well, you can cut it at a different point above all rust, and then weld that in as you would your quarter.

I never split the seam at the rocker when replacing with a skin, if you do there is nothing to weld the skin to since the skins dont have a flange at the bottom. Cut the old panel about an inch above that seam and that will give you plenty to weld to. Also make sure and cut the rear lower flange off after you weld it to the trunk drop off, most of them hang down too low and make it obvious that the car has had a skin put on it.
Ron