Hey guys,
Yes, it is a 1990 ZR1. So now I understand:
1) CHMSL has a dedicated switch on the brake pedal. Now there's something I wouldn't have thought of!
2) 2-DIN head units will fit if you do quite a bit of trimming / sanding to the head unit. I guess there's not a lot of market for a 1.5-DIN unit.
3) No keyless factory-installed. I'll need to add that aftermarket (since I'd rather not be dealing with keys that can scratch it!)
Thanks much! I'm looking forward to getting to know more about these cars.