That's a cool color combo, green guts with Olympic gold paint.
Reading this info from chevynova.org, will explain some things about your sheet:
http://chevynova.org/BroadcastSheets.html
Did it have a rear window defogger? I ask because RPO C50 is a defogger. This next link will help with the RPO codes on the sheet.
http://www.novaresource.org/rpo2.htm