The body guy is ready to start replacing my rear quarters. I have the quarters, the trunk drops, but need outer wheel wels. Our thought was to buy 73 mustang and alter, but I'm a novice so I can't speak too intelligently about that. Is this a reasonable way to go?
They are not reproduced and full Mustang housings will not fit worth a crap. I have used the lower repair section from a mustang but it took considerable massaging to get it useable. Best bet is to try to repair what you have or find used ones, which are almost impossible to find in rust free condition.
Outer wheel wells can be rebuilt if they are not too badly rusted away. We rebuild them all the time here simply because the road salt eats them alive and because you can't buy them.
I have also used the lower outside wheel house repair panel from a Mustang. I did not have any problems with it fitting. Not a direct fit, just minor work to get it to fit.