How Difficult to replace Extension housing?

I spoke to Jammie @ Passon Perf. Here is how it works..I'm using the cast iron housing,short tailhousing and cluster gear shaft from the 1:1. I'm then installing all the O/D internals and a shorter O/D mainshaft(that I got from Jammie).Should be about as strong an O/D 833 as you can have. I'm keeping all the 1:1 internals in case I ever want to use them.