What setup are you guys running on a 302? My headers hit the shock tower, on my regular manifolds are hitting the gear box at the flange.
Seems to me you don't have correct headers for the car. I am running Hedman shorties, before that I had long tubes, neither hit the towers or gear box.
if stock manifolds are hitting anything you could have wrong exhaust manifolds, wrong motor mount stands/ on wrong side or wrong motor mounts.
After I figured out the frame hangers we're on the wrong side, it helped with clearance. The stock manifold on the driver side still wants to touch the gear box. I may just order another set of headers and see if that fixes it.