I ended up throwing it away after totally screwing the gauges up on re-assembly. Here's the problem... You pop the needles off like the hands of a clock, but the problem is that when you put them back on, the stems that poke out of the dash that hold the needles are extremely easy to turn, and therefore none of my gauges were accurate anymore. Moreover, the thickness of the overlay caused some of the needles to stick and kept them from moving properly.
I ended up buying another instrument cluster from a scrap yard to replace the original with.
My advice - Buy a scrap cluster off of ebay to play with... When you get it right, put it in your truck. These things are TROUBLE!