Since I had my 91 LX the parking brake has never worked before...The handle pulls right up and thats about it...What are the main components that could be the problem causing the parking brake not to work?
cables can fray over time, and as they fray they lose tension. The more they fray, the easier it is to pull up on the handle and the less they hold the rear brakes. Eventually, if they are frayed they just eventually break into two pieces and you have no e-brake until you replace the cable.
There's a good chance that the mechanism of the lever itself has gone bad. When I first got my '90 you could sometimes yank the lever to almost a 90 degree angle. The self-adjusting mechanism in them goes bad and it doesn't engage properly.
As far as the cables go, just crawl under the car and check them--the cables are really easy to see.
just fixed mine the other day. on mine it was the short cable from the handle to the equalizer, which is a ford available part only. then you have a left and right rear cables that are available at any parts store. Just crawl under and take a look, it only took me about ten minutes to fix mine. good luck