I was at another SCCA event tonight, and confirmed that changing the ride height puts me directly to the modified class, along with cars that have high levels of modification to the engine, wheels, tires, etc. So changing the ride height is a definite no.
They also confirmed that if I alter the interior for weight reduction, I will be automatically bumped up the the modified category as well. I would be able to take my rear seat out because it is easy to put back in for events, but that's about all I can do for weight reduction.
Even exterior mods are questionable... even though it is an autocross course and aerodynamics don't give an advantage, some could argue that ANY aerodynamic modifications are classified as "exterior body mods" and bump me up the the same category as the other two examples above.
