Mark, Is this a 2WD truck? Yes it can be done, but it would seem simpler & better to just get the TH400 rebuilt. If it is a 4x4 you need a different transfer case. I would think for $500-$600 you should be able to get the TH400 redone. To put the TH350 in, you will need to change the yoke (maybe the driveshaft depending on which length TH350 you have) move the crossmember (maybe change the mount) you will need the TH350 dipstick & tube & install the kickdown cable. Lorne