So, I've made some progress. I've been making the mount for the adapter plate. Last night i mounted the whole thing in the truck. It was close. VERY CLOSE. But it does fit. Has about 1" of room on all sides and works wonderfully with the gas tank. Instead of making a cross member i decided to make a piece that goes from the front cross member to the rear. I don't see any blaring issues with this, so i hope it works well. It was a bear to get in there, and had to come in from the gas tank side in order to fit. But i actually think this might work now. There are still a lot of smaller issues to work out (such as the modification of the front cross member) but seeing it in the tunnel actually puts a light at the end of the tunnel.

Something to note- this mod would have never been possible without the 3" body lift. There simply would not have been enough room in the tunnel for the 2nd t-case.