I have rebuilt my gate once and the results were quite nice. And if done properly will last a good long time. I actually like the roll away window and am not a fan of the truck tailgate change (unless you are running a soft top

).
Everything on the tailgate can be removed without cutting anything. The key to ease of removal of all parts is to get the window felts out of the way. These are what fills the gap between the glass and tailgate. once the inside and outside felts are removed you can then pull the glass out the top after disconnecting it from the regulator. Then remove the regulator.
Once the glass and regulator is out you can remove the tracks from the access hole in the face of the tailgate.
I have found that a quality rebuild must include replacing all the weatherstripping and felts. The weatherstripping is key to allowing smooth operation of the glass and protecting the glass. Most broken tailgate glass results from loose felts, bad glass channel felts, etc. If you close your tailgate and hear glass rattling then the felts and channel runs are shot and need to be replaced. The gate closing should sound like a nice quiet normal door closing.
I prefer NOS parts but they are getting tough to come by. If NOS is not available then I woudl use
www.classicindustries.com They seem to have better quality weatherstripping that LMC.
Cheers,
Rufus