I know this is an old thread, but I'm doing this now and my heater core is fastened inside the box, not on the firewall like in the photos. There is no way I can the curved tubes in when attached to the whole assembly. Fender has to come off to remove the outer box and allow clearance for the heater tubes.
Last edited by Kyle; 01/09/1407:46 PM.
1968 Firebird, 350 4V, TH350 with trans-go, 69 slap shifter, 8.5 inch 10 bolt 3.42 posi
