iizuka
+1y
I know that this is an old thread, but since you didn't get any info...
The stock B transmission will work if you use the RX7 manual transmission bell housing and modify the input shaft. Your best bet would be finding an RX7 manual transmission and swaping in the tail housing and shifter feet from the truck's transmission to the RX7's. That's what I'm doing on mine. This way, the transmission will bolt right in (using the original mount) and you will be able to use the truck's original drive shaft.
Now, the motor mounts you will have to make your own. If you find anyone who makes bolt-on ones please let me know!