If I understand correctly, I should be able to remove the stock ECU - leave the harness for future reuse if needed - and simply replace the underhood engine wiring with the 2001 stuff. Everything including the tach and speedo should work correct? I don't have a factory boost gauge in that truck so that's not a worry. I've called a few places and nobody really seems to be willing to make me a custom harness. After reading your post, it really doesn't seem like I would really need one either though. For things like the water temp, oil pressure etc. do I need to "t" the wires under the hood so the gauges and PCM can both read?
From reading the forum and looking at my Ty, it seems the wiring between the two are very similar.
Just wanted to see what your thoughts were and if I read that correctly. Thanks.