Ok got it. You seam to know what is required and are skilled enough to do it. Great! An SLC can be made to run a lap time at GT3 pace. If you add enough power I would think it could be made to go significantly faster. The only limitation is that the car is not a ground effect car. It does however make quite a bit of downforce if setup correctly. It won't run IMSA P2 pace but then its a hell of a lot less money.
I have personally witnessed a very well prepared SLC run the 24 hrs of Thunder Hill NASA event and run lap times at or faster than a Flying Lizard prepared and crewed GT3 Porsche and that was on Hoosier R7's with the Porsche on IMSA series Dunlop's. This was in 2017 or 18 I believe.
So the car can be made fast enough to win armature "open class" races as long as someone doesn't show up with a pro built prototype on race slicks, a big budget and a ringer for a driver.
I don't worry about the Aluminum construction. If you shunt it, it will be the same process to fix it. Cut off the bent stuff and weld on new stuff. Same as steel, just different material and welding process.