I don't recall having to remove any gaskets.
One thing also on the A-pillar covers, they come off by kind of rolling/sliding them toward the outside of the cab. In other words, toward the door. If you try to pull them straight away from the A-pillar you will break off the plastic clips. The metal clips Jay is refering to are actually welded to the metal pillars themselves. The clips that will break off are plastic and are held on to the cover by melting the plastic cover. You'll see what I'm talking about when you get them off. I successfully glued mine back on using a glue called "Goop". It's in a little blue tube and I got it at a hardware store. They're on there better now than they were from the factory. I've had my covers on and off several times since without them breaking back off.
You will have better luck with the overhead console by gently pulling it straight down out of the clips than sliding it. I broke mine trying to slide it.
The pillar covers in the back do pull straight away from the body and kind of clip over the door seal.
The dome light is removed by prying the clear cover off with a screw driver in the little slots and then there are 2 screws holding the base to the roof.
I would suggest removing the center console first, then the passenger handle, coat hanger, dome light, then the A-pillar covers then pulling the top of the rear covers out. Don't try to remove them entirely and let the back of the headliner rest on top of them. Then finally the visors. There are also some velcro type things over the driver side door and a couple on the roof, so don't freak out when you feel them holding it up.
Lastly, the headliner board itself will fold if you try to bend it too far and then it's pretty much shot. Pull, pry, and bend on it carefully.
The material I used was the same as the factory stuff and went on real well, but I have heard of others using camo material or other things so don't be afraid to be creative.
Scott