1986 Chevy Camaro distributor

Electrical problem
1986 Chevy Camaro 6 cyl Two Wheel Drive Automatic

hello I own a 1986 camaro im restoring it and well I got no spark to my plugs so I put a volt meeter on my coil it reads 12volts so I took my distributor cap off and the thing that meets up with the spark plug wires and coil wire it turns slowly and it does not come up it stays down below keep in my thign car has been siting for 3 years could it be rusted down if so how much of a pain is it to change one and could I destroy my engine if I do it wrong