I think it's because the line shift bracket that connects to the pan would hit the header flange?????
Thing I hate the most, is when they say things like the A-body headers are compatable "and fit" with stock floor shifts, "then" they turn around in the directions and say that you have to modifiy (cut & weld) the trans bell crank (shorter) as well the shifter support link by cutting and welding :angry4: I think if anyone has to start cutting and welding for parts to fit correctly or clear....it's "really" not a fit. I'm just crabby...and think these two parts should be supplied for installation!