One of the main reasons I'm thinking about changing trans is because the 904 appears to be original to the car and definitely needs a rebuild. Also the converter definitely isn't sized correctly for the current engine so I'll need to be buying one anyways. I'd prefer to have a 4 speed just for the experience if anything.
With the budget, I figured I'd be looking at around 1ok for a build, which I'm okay with. The car needs a new engine one way or another and I prefer to put the money into building something good rather than just a rebuild of the 360. Thank you for the info.