Goerend Transmission
I have heard a lot of good things about Dave Goerend. When I needed a transmission for my 94 Dodge gasser, I went to Dave. He is located about 2 1/2 hours from me, so I made a trip to his shop to pick up the transmission. I had him build a transmission for me, like he would a diesel truck but with a higher stall convertor and governor for the gas engine. I have been really happy with the driveability of the transmission. What I like is that it is a firm shift, but not neck snapping like the shift kits are. They ship trannys all over the country and probably outside the country, also. I am sure some of the other companies you mention do a good job, too. My 96 Dodge Cummins has a 5 speed transmission or else there would be a Goerend transmission in that truck by now. If I buy a different diesel truck with an auto transmission, it will get at least a Goerend torque convertor, right off the bat.