Hey Everybody! So I was trying forever to sell my 2000 2WD 4 door chevy tracker but got no hits. So I've decided to try and do a 4WD conversation to it. Harry's write up on 4wheeler gave me the idea lol. https://www.fourwheeler.com/project-vehicles/1506-we-build-a-lightweight-fuel-efficient-daily-driverrockcrawler-chevy-tracker/
I've already have a sammy t case lined up and will be getting a FJ80 solid axle from a 93' land cruiser next week. My question is will a automatic 2WD transmission work or should I swap that out as well?
Tia!!

I'd say you can use either a 2WD manual or automatic transmission - the main point being that you need a 2WD transmission to go in front of the Samurai's divorced transfer case, rather than the 4WD transmissions which have the transfer case attached.

Be aware that you're looking at a lot of custom fabrication work, your question suggests that you may not have the experience to work your way through any trouble spots that you may run into, so make sure your wallet is deep enough to pay the folks who do.  Track down ALL of the various articles (I think there were about eight) and read them thoroughly, I believe you'll find that the finished product deviated quite a bit from the original concept.