Use a soft wedge to seperate the top of the door from the cab. You can open it enough without causing damage to stick a peice of metal like a coat hanger rod in to grab the door handle. Or go get a slim jim. An 84 aint exactly fort knox. Probably take 30 seconds to pop the lock even with zero skills. Third, go find literally any ford key from the same era. Jam it in the lock and wiggle it.... They are usually so worn out any similar key works with enough wiggling.

 

yup - half the time any ol car key works. my 95 s10 was so worn out my 02 blazers key would unlock it and my 1980 chevettes key(only cut on one side not even dual sided lol)

if its got a sliding rear window slip a small screw driver in between the the panes and open the latch.

 

the police in our town will actually break into your locked car for you! they keep slim jims in their cruisers, lol.

 

Yes, a Slim Jim

Google: how to open car door with slim jim

You can make one from old hacksaw blade or any thin metal strip.

I used a paint stir stick once, but was older car so larger gaps