where can i find technical information about the rear differential on a 1980 corvette ?

Answer 1

I don't know what sort of "technical specs" you need, but most anything that can be repaired or adjusted can be found in a repair manual. If you need more, go to Chevrolet and order a shop manual (NOT a repair manual).
You might try the library in the REFERENCE section. While you are at the library, ask if they subscribe to either ALLDATA or Mitchell On-Demand. These are professional level resources, computer based, independent shops subscribe to them.
Or, if you like, go to one of these links. It is the same information data, but for only one car at a time, available for a subscription, monthly or annual.

http://www.eautorepair.net/
http://www.alldatadiy.com/

Good Luck