One thing I can tell you. The extension housing swap on the 545 is easy peasy. They just unbolt from the back. The two wheel drive housing has the output shaft in it already. It just bolts back on to the trans.
I watched a video about tearing a 545 down just in case I find out that it's smoked to see if it required special tools to tear apart. You'd think I would have remembered that the entire rear shaft just unbolts and comes out..... Thanks for the reminder! I guess I'm just so used to GM transmissiost where you better find the correct transmission because swapping an output shaft requires a complete transmission overhaul. Thanks again!