Cab changes in Bullnose

I'm trying to find out if there were any dimensional changes in the transmission tunnel/firewall from the previous generation to the Bullnose. I'm going to be putting a 7.3 Godzilla with a 6r140 in my 86' and I saw where someone did this with a 79' and had to do a little bit of tunnel modification for it to fit.

I don't know the answer to that question for sure.  However I suspect that the earlier covers will not fit a Bullnose.  That's because all of the Bullnose and later covers were developed in 1980 or later, as shown by the E0 and later prefixes on the part numbers, as shown below.  But the later covers do fit a Bullnose, such as the 87 covers for a manual transmission which are taller because of the height of the ZF5.

By the way, you'll get better help if this thread is in the main section.  Ok for me to move it there?

I hope you start a build page, this sounds like a very cool project!