I'm looking at an 87 f150 with the rear sliding back window. The back right pane is busted out. Would it be very difficult to just go to a junkyard and get that pane or do I need a whole new peice.

 

Installing Back Glass | FordMuscle.com

 

You have to remove and disassemble the whole window to replace that one pane.

I would just change out the whole thing

 

You can change out the whole window with a flat head screwdriver, my buddy picked one up for 35$ at a pick and pull junk yard a while back

 

You need more than a screwdriver to reinstall it

 

That's all we had used, maybe more than one but all we used were flat head screw drivers and our hands

 

Yep, the whole thing has to come out to replace that pane. Learned that the hard way myself. You can probably find it, but as you have to take the whole thing out anyway, you might as well look for an entire window to replace. Twine, twine is your friend when it comes to the seal! LOL

 

A string, and a can of Go-Jo, or some "personal lubricant" to ease the seal into the opening.
You want something you can wash off with water.

 

I did last summer. Two flat-blade screwdrivers to take it out. It's easier with the sliders open, it allows a bit of flex. Put it in with twine and dish soap.

 

Just some food for thought.

It takes LESS than 30 second to put the rear window back in with a 15' piece of string and ZERO risk of scratching the paint or breaking the window like a screwdriver will