I think it should, but don't take my word for it.
What I do want to say is that switching transmissions is gonna be way too much trouble and money.
Get a 4R75w (from a late '03-'04) and get it rebuilt with a J-Mod and/or shift kit...assuming you have a 4R70W which I'm pretty sure you do. The 75W's were built stronger, but is essentially the same transmission.
I don't think there should be a problem because I was told that the pre-'99 models had a mechanical speedo, which I would think would eliminate the need for tuning...but I may be wrong
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Sadie- '04 GT Auto- RMR#4837, 4-Point-SEXY