dealwithit
+1y
if you can find a trans from an N/A rx7 either first or second gen (fb or fc) they have better highway gearing in 5th. i swapped to an fb trans when i built my f2t truck. its relatively simple with basic hand tools. first aquire an rx7 trans. then unbolt the bellhousing from the center section. when you go to pull it off it will require a fair amount of pressure down on the input shaft to pull the bearing out, but be careful not to beat it with a hammer directly, you can brinnel the bearing races and cause them to fail down the road. once the bell is off you need to do the same to the truck trans as you need that bellhousing to put on the rx7 trans. make sure to seal the joint up with some good RTV silicone. once you slide the truck bell onto the rx7 trans you can pull it together with the mounting bolts. just try and rotate the input shaft while tightening. next you need to swap over the tail housing, which holds the shifter. when you get both tail housings off you will also need to swap the shifter feet, just make sure you swap them over into the correct location. the feet are held on with little roll pins that need to be punched out (dont punch them all the way out as they can be hard to get started again). you should also swap over the plastic speedo gear on the output shaft too as its calibrated to the rearend. once that is all done you can slip the tail housing back on, i think theres a limiting bolt beside the shifter you need to remove to allow enough side movement so the shifter arm can get slipped into the shifter feet, then reinstall the limiting bolt. now install the shifter in the trans and verify you can get into all 6 gears (1-5 and reverse). turn the input shaft at the same time, and verify that everything turns and works without to much noise. If everything is all good then reinstall and enjoy a stronger trans, and less rpm's on the highway