Hi, I recently rebuilt my 1988 Trooper II engine, and I am now hooking the transmission back to the engine. There is one bolt hole that doesn't seem to want to thread in. This bolt is the ONLY one that threads into the transmission from the engine side, all others go directly into the engine block. I am wondering, could this be some strange american thread? I tried going to the junkyard and threading one of my bolts into a similar transmission there, and it did the same thing, it just doesnt feel right. Any help would be very appreciated.

1988 Trooper II in the works.