?\'s on swap from a/c to non a/c When I swapped the drivetrain from 1/2 ton to 1 ton and threw in the bbc, I also did some rework to the plenum on the firewall where the blower motor is because I wasnt going to use the a/c anymore. I hacked part of it off because I was told I didnt need part of it anymore, but now I get no heat at all. I cut off the part that is closest to the middle of the truck that covers the last hole in the firewall and just covered that hole up w/ sheetmetal. Everything has been replaced, not sure what else to do. Should I have left the plenum on the firewall intact? any input would be appreciated. Thanx.