You sure you want to go down that route? You're going to most likely end up in SSM class. Good effin' luck. I'd say if you're not winning SS consistently or at least getting 2nd place, I would start with getting absolutely everything out of the car first.
I'd maybe talk to @David@Borla as a start and see how they finagled their exhaust systems. I think that's still a little under complicated but maybe not.
The magneride system is great if you want a street car that can go very fast on the track, but for pure track performance its hard to beat a set of properly setup coilovers
E92 M3's and Alpha Camaro 1SS's are the ringers right now. A GT350R in rawest trim at 3655lbs does have an advantage to a degree but but holy hell is the classing not to your advantage. FS indexing is hilariously light in my opinion.
$70k did you get a discount? lol
Did you do Toledo this year?
Yes, you can, but you have to fool the control unit into thinking that the dampers are connected when they're actually on a shelf in your garage. To do that, you'll need a way to put resistors of the correct value and heat capacity across the wiring that runs the Magride dampers.