A904 has reverse no foward

Well, I had the trans done when I swapped out the slant 6, so last summer I drove the car and was fighting a different issue, so this is a new issue, I was driving to work when I got it to about 50mph, then it quit going, from that point I had to stop the car wait about a minute, then restart and drive about 1/4 mile, then it would quit moving, rinse and repeat till I got home, after that is when I pulled the trans out etc. come to think of it, would there be a difference if I swapped out the VB from my slant 6 a904?