I am going to take your guys advise and stick with the 4l60.
I don't have the trans to t case adapter yet so I made a mock up adapter today.
I forgot about the thread I started about 4 link design and I went back to re read it. There is a few things with my rear that I didn't like so I am rebuilding some different link mounts. My uppers were longer than the lowers and the triangulation of the uppers and lowers weren't parallel. I also think I can move my upper frame end down a little when I shorten them and get them completely flat at ride height. Hopefully tomorrow I can get it all reworked.