Hi, good to see you are spent time in your garage.
Big rims like a 17'' - 18'' is a good choice if you want to use bigger brakes. Maybe on the 1/4 track would 15'' be a better choice.
17'' is good, it is not too high looking on a C2's. Wide 15'' steel rims would be coolest way to go with your 66 on street if I understood right your idea. Low 66 bb with a wide tires is just so hot.
Do you really mean 15mm bs,,,,, or 115mm ?
Original seats are also good looking but not very good on a circle track if you do not remember belt yourself very thing on the seat. The VIN of your 66 is a early 66, the seat belt buckle decal is used 65 and early 66 only.
The white 66 sounds good with those pipes. Maybe too loud on the street?
How heavy (or light) the bare frame was when welded and ready for the other parts, did you weight it ? I mean just the frame without any parts on it.
SS trim parts looks very good. Did you use new molding clips? that will help for installation.