360 kevco pan hitting drag link and pitman arm with headers no steering

What mounts are you using i.e. solid, stock, Poly? That part of the pan is the stock stamping so it should clear. It looks like both your pitman and Idler are placing the steering link level. So either your mounts are messed up or you have the wrong pitman/idler combo. Was this all on the car when you had the 318?

I just looked at my and my 340 with Kevco pan has about 2" plus of clearance between the link and the pan bottom.