Stooooooop! Noooooo!
Dont remove the door skin its not neccesary. The ONLY thing you have to remove to get at it is the inner door trim panel (obviously).
I've changed out the locks in my 85 se and its really not that hard.
(This is all in the perspective of the PASSENGER SIDE door, reverse for the drivers side)
Roll the window up as far as it goes, it'll give you access to everything inside. (if you're feeling adventurous you can remove the window guide as well. Its a channeled piece that's right in the way of everything, just remove the top two bolts, and the bottom two bolts (SCRIBE YOUR NUTS!) rock the bottom towards the front of the door and pull down and away from the window. The window has a wheel that goes in the channel in the piece you removed, clean and grease it before you put it back)
Take the inner door panel off (two screws in the handle plate, one behind the fiero snap in thing, the other behind the end of the handle. 3 screws in the oh **** handle, one in the top behind a snap piece and two in the bottom) Just pry/pull the panel off, it comes off. CAREFUL though, the lock rod and release handle rod are still attached to it. Slide off the handle plate from the handle. Pry off the lock lever thing (fuzzy deal with red on it)
Set the panel aside
Take the "Lock rod retaining clip" off of the lock arm. If you look inside the door where the lock lives you'll see a long rod coming from the handle to the lock cylinder. Take the little clip off thats holding the rod to the lock arm. CATCH THE PIECE! Its tiny, and it likes to hide in the door skin.
Pull out the "Lock cylinder retaining clip" If you look to the left of the lock cylinder, right long the verticle piece the lock cylinder goes through, you'll see a little tab sticking up. Pry this tab to your left, it's a horseshoe shaped clip that pins the lock cylinder up against the support.
Once you have the lock cylinder out, swap the hardware over. It IS position sensitive, it makes a cross shaped outline with one of the tabs sticking out further than the other. It goes in only one way. If you have trouble with the lock arm and what way it goes, remember how it used to go, it should swing off to the lower left when in the door.
Put the new lock cylinder back in where the old one was, oriented correctly. If it wont push in all the way its because you have the wrong lock shield on it (little spring door, it sticks out too far and bottoms on the door skin, i just took mine off)
Slide the "lock cylinder retaining clip" back in, making sure to pin the lock cylinder in. If you dont think its in, push on the lock from the outside, it should be solid.
NOTE This part is a PAIN IN THE ASS it's supposed to be hard. Dont give up, just keep trying, it DOES go together like this
Put the lock rod back into the hole on the lock cylinder lever, put the clip back on it
Rattle your work around, push on the lock from the outside, pull on the rod (not hard though) it should be totally solid. Try the lock out, does it work? Good!
(if you removed the window guide, replace it at this time, its a hassle too but it goes on, just pop the window wheel in the guide, line up your scribe marks (you DID scribe them, right?) and tighten her up

)
Put the door trim panel back on, slide the handle and lock rod through the hole in the side of the panel, hang the panel on the top of the door while you work
Slide the handle trim plate over the handle and make sure the lock rod sticks through it's hole
Slide the end of the lock lever button thing (red/black thing with fuzzy on the back) into the hole it goes it sliding along the rod, snap the end over the L on the end of the lock rod
Install all your snap connectors/pull the broken ones out of the door matrix and reinstall them
Screw in the handle trim plate
Screw in the oh **** handle
You're done

I've done this twice before, yes its a pain in the ass, but not too hard.
NOTE: You have to have smaller hands, or be willing to lose some skin, because the procedure with putting the lock cylinder retaining clip requires you being elbow deep in sharp stamp steel.
Good luck

[This message has been edited by InaneCathode (edited 08-24-2007).]