just purchased a '79 coupe for my 16 year old son and myself as a project. We stripped the paint and sanded all we can, but we cant seem to figure out how to get the door handles off, the door locks off and the doors off themselves. The other mystery is how to get the miirors off. We are about to take a cut off wheel to the inside of the door to make more room to work. I feel like an idiot not being able to figure this out. Any help would be appreciated.  

pd,
Concerning your doors. DON"T i repeat DON"T use a cut-off wheel on the inner panel. It is very tight but there should be ac access panel on the inner panel frame of the door.
Your Handle should have 2 bolts holding it in, going in from the inside of the door with the window glass up. You'll have a plastic elbow clip holding the rod to the handle connection to open the door with.
Your door lock should be of a similiar arrangement except it will have a thicker U clip (similiar to the Air Breather clip in 60's GM V8 air cleaners) in look. This will fit betwen the lock and door and can be a pain to remove.
Your mirrors should be able to be unscrewed inside the door but I'm not positive as I've never had to work on those on my '79.
The doors will have a Big Square Spring Clip (should have...lol) that I'd recommend you use a speciality tool to remove. Than just tap the door hinge pins out and have 1 or 2 friends handy while doing this as it can be both awkward and become heavy if just 1 is holding it.
Good Luck and CONGRATULATIONS for both you and your son on the project together. Working.... Rebuilding.... Driving.... will all create lifetime memories for you both.  

Congratulations on getting your '79. Try these things for your questions:
1) The door handles should have 2 threaded screws holding them into the door skin. Try locating 2 nuts that you remove to take the door handle out. There should be a plastic elbow clip that will be holding the door rod to the door handle. This needs to be removed as well.
2) The door locks will have a similar arrangement with the lock rod and the plastic elbow clip. Plus there should be a U shaped clip (similar to the air breather clip in the 80's air cleaner base) that will be holding the lock to the door skin. This needs to be removed... than remove the lock.
3) The mirrors should have 1 or maybe 2 screws plus the directional mechanism needs to come out with it (if it power mirrors) I'm not sure on the mirrors as I've never messed with them on my "79.
$) The Doors. DON"T ... please DON"T ever cut a hole with a cutoff wheel in your inner door frame. It is VERY TIGHT at times... but its a Vette, ehh. There should be a thicker spring that should be installed in between your door frame and the A pillar frame of the Vette. You should use a speciality tool to remove this. Once it is out, there should be 2 pins holding the door brackets together... or 1 pin and a bolted bracket. Remove the pin(s) and have 1 or 2 friends there as well as your son to hold and guide the doors from the vehicle.
Congratulations for you and your son... on this project. The memories you share in buying.... rebuilding/restoring..... driving.... this together.... will last a lifetime.... for you both.
Good Luck in your project.