I have an 86 Z28, the deck lid will not open either with the key not the electonic mechanism. The key seems to engage properly and the electronic switch makes an actuating sound but the lid refuses to unlock. Does anyone ave any suggestions as to how to get the lid open without damaging the body?

You have to crawl from the inside and pull the center interior panel back or loose and reach in and pull the latch down manually with a screwdriver.

It sounds like the gearbox is broken, or at least the gear case is broke. GM made it from plastic and the case will break. GM sells the case for like $30 USD, one can transfer the gears and motor to the new case. If you need a new transmission, it'll be more bucks, Like $120 USD.