2000montana

I have a 2000 Pontiac Montana and a few weeks ago my transmission (4T65E) failed so I replaced it with a transmission out of a 2003 Pontiac Aztec. As far as I can tell the final drive / gear ratios are the same, but I could be mistaken. I am getting a fault code of P1810 (TFP position sensor) from the PCM and it is also getting torque lockup occasionally. Apparently sometime in 2002 the TFP assembly was updated (TSB #020730050) and I am concerned that my PCM need to be reprogrammed to accommodate this change. The transmission is in what I presume limp mode and I don’t get top gear. Although on one particular day (just as the first fault code first registered) it was shifting in all gears. Hopefully you can help with the above problem.