[davepl]

I doubt its the case here, since you still have the small block, but I know I once tried to install headers in a '69 B-Body that still had the small block pedestals but big block mounts. Nothing cleared.

I've also run into major issues with my 502 Camaro - but that's because the exhaust ports are raised on the cylinder heads.

Since you seem to have an otherwise stock collection of parts, something (like the pedestals) must be in the wrong place. That or the truck used to be a big block and it has the wrong stands, but I don't even know if you could make that work in these trucks. That kickdown part has me stymied though.

The older I get the more I like stock manifolds. Sure they eat power, but how much traction have you got in a pickup truck anyway?