I think you're selling yourself short! I had to do more welding because of the previous 4 speed conversion, for a straight auto to T56 it would be a little easier. I'm not some master bodyman either, I did all that welding with a 1971 Millermatic 15 with a Tweco gun conversion and Harbor Freight .030 wire, it's definitely NOT high tech or the best sheet metal set up. And no sheet metal tools or anything, just a couple hammers, dollies and clamps. I also wasn't trying to keep the tunnel small, if anything I made it larger than it needed to be in a lot of places so I would have easier access to stuff from below.
Here'e a picture before I added the console, this a 4 speed carpet (the hole is from the old 833 shifter location). Needs a vacuum and my fan controller tucked out of the way but you get the idea.
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