Hi, I putting a GN motor in my 87 Monte, Im making it mostly a track car but I'l still be driving her to car shows and cruizes...Im using my built th350 trans with my GN motor, I found a BOP adapter plate but I just wanted to make sure it will fit, the member selling it used it for adapting his GN motor up to a th400 trans, doesnt the th350 and th400 have the same bolt pattern, I have the chevy bolt pattern on my th350, I just wanted to make sure before taking my motor and trying to bolt it up, Id hate to be stuck in that situation, any info will help, thanks