I have a 67 Firebird 400 Convertible, 4bbl. It has the 3 speed automatic transmission, PB, PS, PW, Power Top and AC My engine code is YF, instead of the YT which I believe should be correct for that transmission. I am assured this is the original motor and have done some research and found on the Hemmings site that the YF was indeed used on the 67. I have submitted for the PHS docs and have not received them yet. I have emailed the PHS and he said it should be a YT code. Can somebody please give me some info?