That GT is a bad bear! Nice video.
I was doing a mix of AX and track days with my Lister. I tried R6 Hoosiers but the tire I actually liked the most was the Kumho V710, which I guess is now supplanted by the V720. It seemed to offer the best combination of predictability and grip. It also wore like iron but with a 2,000-pound car tire wear was never going to be a big issue. I was using the same tires for AX and track days.
I certainly understand not wanting to touch the bodywork on your car. Before I settled on a roll bar-mounted wing, I was looking into fabricating one that actually mounted inside the trunk. But that would be difficult with a Cobra because the trunk lid is cut so far down into the rear bodywork; on the Lister the opening was at belt-height so it was a more viable option. I don’t know how you’d be able to mount a splitter on the front, given the
oil cooler opening on the chin, and you’d have to run your support stanchions through the fresh-air vents or something. Not easy!