Chrysler went to a new design wiper motor in '84, that looks like this:
There are quite a few different versions, but most will '84 and newer wiper motors will interchange.
If you get a motor from a parts store, you will need to transfer the mounting bracket/plate to new motor:
If you notice, the top picture has a external (but attached) electronic part on it (with a missing cover), where as the picture above does not - but both motors will interchange. The version just above has the electronic portion inside the cover.
The motor that
@XfbodyX pictured is for an '76-83 FMJ (depending on 2 or 3-speed version and if delay wipers or not). It will require a new pigtail and re-wiring to fit.
With that said, I think I know someone looking for a wiper motor, just like the one you have,
@XfbodyX.
I hadn't weighted them, but would bet a single US dollar the '84 (and newer) version is lighter than the older ('76-83) 2-speed, 2 speed with delay or 3-speed wiper motors are.
BudW