Rob, I would respectfully suggest that your car is probably capable of 2:10 to 2:12 at VIR. I think that is around the AS track record?
If so, at that speed, you are between 5 and 7 seconds off the normal GTA/1 cars. However, you would be 10 seconds plus FASTER than most IT7 and A cars.
There is no bias in SCCA against your type of car. Well, not sure I totally agree with that given the "issues" we are having geting the V8 ponies classed in ITR....but let me rephrase....your car as an ITO car -- like any ITO car -- is in a catchall class. Since the numbers of participants are low, you get stuck in basically where you (a) fit and (b) cause the least "trouble" from a time difference perspective.
I just think you happened to pick a car to race that right now, SCCA does not provide a good fit for class wise. AI in NASA is probably a much better fit.
Hate to lose you, and hope you build an ITR Mustang when they get classed.