4 Cylinder Fuel Pump Replacement

You bring up a good point - now that 4 cyl AMCs are becoming more collectible, there really should be a section for them.

The motor you have is the GM sourced Iron Duke, so you should be in very good luck in getting parts for it, as there are plenty of them still in service in a broad range of GM products.

As for the door handle, that's a relatively easy one too - the Concord uses the same door handle as Gremlins and Hornets all the way back to 1970, and eagles through 1988, although there were minor finish changes over the years.  If you're not picky, junkyards are still a good source.  If it's only the return spring that's broken, those do pop up on ebay from time to time, and the usual AMC parts sources have them in stock, as well as paddles and complete handles.  The handles are handed, so you'll need to specify left or right side.

All the EFI models do, but the carbed models have a block mounted pump. See this to replace it:

You won't need any special tools, it's just in a hard to get to place. Might be a little easier on the Concord since the 4x4 axle isn't in the way and the crossmember is different than the Eagle. Scroll down and read all the replies, a guy called "Happy Pappy" posts that it's not all that hard, but alternator has to come out to get to the fuel pump easily.

I had an Iron Duke Spirit as my daily driver for exactly one day.

Flames were literally shooting out from behind my rear bumper when I blew the engine.

(tow truck driver told me he saw me drive by "looking like the Space Shuttle" <-- his words)

Fire trucks and everything. 

Not a fan 

Edit:

Welcome to the OP,

not trying to sound negative, just putting out my short lived experience