Collaborative early a experiment

Just my 2 cents. I don't have a V-8 narrow body.

If you are going to modify stock style exhaust manifolds to fit, 1/32"-1/16" clearance is just too tight. It may work for one particular car but if the same manifold is tried on a different car, you may have 1/4" clearance or 1/4" interference. In my opinion, you need to "kill" the problem and err on the safe side.

Angle milling a mounting face may help, I don't know, but depending on how extreme the angle needs to be, you may want to spot face the bolt head area so it parallels the face.

But the info you are gathering is a great thing to have and share.