Q: Short output shaft 727 w/a Gear Vendors into a '67-up A-Body?

I run a 904 GV setup in my 67 Dart. The trans you have will work with the kit. The trans mount does not change location. You remove the existing tailshaft housing and install the GV tailshaft adapter. The GV coupler then slides on the existing trans output shaft and you bolt on the OD unit. It got tight in the hump area above the OD unit on my car and I didn't want to change the drive angle (tailshaft down) on the motor/trans, so I cut the tunnel up top and made a panel for the top. With you short trans you probably won't have to do that.
I bought my unit used and it works great. The electronics did not work on the used unit so I wired in a simple momentary switch to switch it on and off. I run 4.10 gears and the OD knocks off 200-300 rpm on the interstate @75mph.
Literature attached you can read up on.

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