Any ideas for brackets, so this doesn't twist backwards? Not sure about regular U Bolts for this reason. Where can I get billet brackets (1.5" diameter roll bar)?

thanks in advance as usual!

I presume you mean an aerodynamic type wing that gives down-force, if so, you will either have to weld some sort of mount to the roll bar that is strong enough to resist twisting (and make sure that the wing itself can take the forces in the mounting area) or take an adjustable strut(s) from the rear of the wing to a strong point at the base of the roll bar to triangulate the loads which can be considerable. Once the loads are triangulated then you can use U- bolts for the main mounts.

There we have it: just use another two mounting spots and it should hold. Thanks!

Yeah sorry, there is only one type of wing where we live, unless we are talking about chickens.

The other type of wing is what Americans would call a fender.

ps - remember that aero wings can generate huge forces and any mounting must be strong enough to survive - one thing you don't want is for the wing to tear loose or flip and generate lift instead of downforce at speed - this has happened before with disastrous consequences.

At autocross speeds I sincerely doubt that it will generate any significant forces. It is just for looks, as will be the diffuser. Since my car has no hope of even starting and running for the foreseeable future, I am fooling around with things I can actually accomplish.