The bushings that are being talked about in this thread are on your truck. They are at each pivot point of your wiper linkage under the cowl.

 

I have a 92 and they do have the bushings on the wiper arm assembly. I had to take the cowl off and replacement them all myself. I was quite proud of myself. You can get those from your local auto store, they only sold them in a assortment pack so I have had to buy two packs to have enough to redo all the bushings.


As for the tab, not sure about an 87 but on my 92 its pretty obvious. You just pull up the wiper blade then pull out the tab (it doesnt go that far out and sometimes you may need a flathead) be careful though they may bend or break. Once that tab is pulled out, you can let the blade down and it shouldnt go down all the way (due to resting on the tab) then pull your windshield wiper straight off. I found it easiest and safest to do by sitting on top of the hood as to make sure to pull them straight out.