Am i right in ASSuming that the minimum effort way of doing this in my Gen2.5 would be to just dump in a non-MIVEC 6g75, and then bribe one of you guys to flash my ecu with some conservative maps, then spend some time with some det cans to make sure it's not knocking? Or would the 3000GT SL ecu be a PNP affair?
You are assuming quite a bit. Motor mounts will need some work and possible welding. Accessories will need some modifications. Likely quite a few other odds and ends pertinent to your montero. You could plug in the SL ecu but the other problem you have is that you wiring harness lacks the proper shielded wire going to the knock sensor. Would have to wire that in. Other than that a 98-99 montero or montero sport would be the best donor vehicle for a MIVEC swap.