I don't know what you mean about the motor mount stuff.. So since mine is before 79 than motor mounts are the same? What are clamshells? Are those the mounts in LMC truck?
I planned on a new HD radiator was interested in the be cool aluminium ones actually. Didn't think about extending wires but figured the altenator would need attention. I only have headers for a 454 (came out of a K5) so exhaust I planned on doing from scratch. Gonna make em pop out just before back tires on each side.