All notchback lids are interchangable with each other. There were two basic styles. The 84 lids had vents across the center and came with solid side panels. All later notchbacks had a bulge over the engine and the vents were moved to the side panel. I have heard that there may be some clearance problems using the 84 lid with some engine swaps. All fastback lids are basically the same and do not interchange with notchbacks. You must vent the engine compartment. Never use an 85-88 non vented lid with the 84 non vented side panels.
These lids remove easily as they are held by two bolts on each side of the lid. Do not try to remove the hinges from the firewall as it is a great way to smash your rear window when the torsion bars release.
[This message has been edited by Gordo (edited 12-22-2003).]