I did mine a couple years ago, new Bilsteins, well worth the $, anyway, I'm assuming you're referring to the front shocks, and yes, it's two pieces. One goes "under" the mount and the other goes "on top" of the mount to create a sandwich.
I found this pic on the 'net. The mount goes in the middle of the rubber sandwich. So you put on one grommet, stick the shock up in place, put the other grommet on top, then put the bolt on
I hope that's what you needed. The back shocks are super easy. My truck even came from "the north" and my bolts all came off easy. The front shocks are a pain in the ass. I had trouble getting that stupid top bolt off. I had to clamp the shock with a pair of vice grips from underneath and use a wrench to get the bolt off... this is one application where I wish I had had the ratcheting wrenches!