Yeah, likely just running Renegade in the foreseeable future. Discussed it with Marc, and while I am technically not legal for STR, the items to get legal are all improving the performance through weight reduction (leather seats, Bose audio, power windows and locks etc converting to a completely base model), getting the Manual rack (which is again a performance improvement), and finding a FED emissions sticker for the hood.
It was possible to buy a 1999 Miata from the dealer with no PS, though PS was defaulted on every possible package, so it would have had to be a barebones one. So if anyone complains, then they would be complaining that I am not as competitive as I could be (because of ~10-40lbs of added weight). The other parts of those packages that matter (diff, wheels) are upgrade legal in STR.
The whole "letter of the law" vs "spirit of the law" debate
I'm not going R-comps, and long before I mod up everything else to get STR competitive I will shift to not being legal for STR anyway. I'm not building for a class, I'm just building for what I want to drive. I just don't want to be flagrantly flaunting a rules violation.