if you changed the pcm and the wiring harness, then you could go with a newer transmission. That would be the worst thing you could do for reliability. the transmission in 94 and 95, built right, is the best transmission you can get in your truck. I am starting to like the new 05 48 re with the added brains in the PCM, but you can't beat the rebility of the mechanical govenor. When you have the trans built, add extra clutches in the orverdrive directs by going with the thinner steels, and have the sun gear and rear planet upgraded in the O/D. Make sure to go with a triple disk, and you will be good to go.