Just out of curiosity, is this just an engine for a project car, or is your current trans going out? Considering it's a 98, best bet would be to stick with a 4L60. If it's for an older project car, you'll need the TV cable and wiring for the 700r4 and maybe a vacuum converter for it. The TH350 will need the same "Kick-down" cable, but with no wiring. There is also the issue of the trans mount, cross member, and driveshaft for a current vehicle. There are a few hot rod forums that talk about this.