bucking as in it gets really jerky and the entire jeep bounces around while/shortly after letting out the clutch?
Sounds like you may have a contaminant on your friction...a.k.a., something is leaking on your clutch disk.
Hop under there and see if anything is leaking out of your bellhousing. If oil or clutch fluid got onto your clutch disk it would cause those issues. You'd have to pull of the old tranny, replace the disk, fix the leak whatever it ends up being, then toss it back together. Not fun