Thanks! It’s a custom overlay from Detroit Muscle Technology (DMT). I worked with the owner Jim to make a pattern for the lower overlay which they now offer. I don’t think he’s doing the lowers in carbon anymore, but I’m sure you could work something out with him if you really wanted one.
Probably about what you would expect, I used the ribs on the E-body can as a guide to keep my cuts straight and just cut a section out and then welded the can back together. I made reference marks so I didn’t rotate the steering wheel mounting studs compared to the splines on the other side. And I tacked it in place and went slow TIG welding it back together, checking that the ends remained parallel as I went.
It’s actually not A-body length either. I took measurements based on my seating position and put the wheel where I wanted it.