Here\'s my 454 sitting in my K20 frame. Before the ressurection (I'm going way beyond restoration), it had headers on it and they had ample clearance. I went back to manifolds to get away from header maintenance. I have since put the cab on the frame and the fit is tight. When it comes back off for sandblasting, it will get some notching done so I can get the valve cover off someday without having to pull the engine. The mounts are homemade so I can't help you there. It looks like it has the same mounts that came with the engine (77 C20) and welded in brackets to bolt them down to. Good luck,
Scott