Help Removing Windows

There's something called canopy glue...at your local hobby store. Used by model airplane builders.

As for gluing the windows back in, I've been using Tacky Glue for that. Tacky Glue works great for a lot of craft and model applications.

http://www.joann.com/aleene-s-...ue-4-oz/2018091.html

I remove them with whatever works.  Cast clear inserts with a small screwdriver. Sheet plastic like many passenger cars a chisel blade in a X-acto handle. 

I glue them back in with 5 minute epoxy....it never dries out.

Some times those pesky windows won't come out without using excessive force which ends up cracking/breaking them or the frame. You just have to mask them off, and that is time consuming.

I recently swapped chassis and bodies of a MPC era passenger set (15") with a more recent set that had finished interiors and passenger figures. The older Lionel window inserts (with silhouettes) just slide out of their sleeves on the sides of the shell, but the modern Lionel passenger cars with finished interiors have clear tinted windows that are glued in to the sleeves at the top and bottom, and are a bit of a bear to remove.

I wanted to reuse the clear tinted window strips from the newer cars, so I used wooden coffee stir sticks, like you find at some McDonalds and at Starbucks, etc., and pushed and worked those in on the tops and bottoms of the inserts, against the metal where the window strips are glued, to free them up, gradually shoving the sticks in and breaking the glue's adhesion.

Sometimes the wood sticks will break in the process, but just pull them out and use a fresh one. It took awhile, but eventually I got all the strips removed (6 car set). The wooden sticks are less likely to scratch/mar the plastic window strips than something like a screwdriver, I found.

Like handyandy mentioned above, I used a very thin bead of tacky glue to attach the clear tinted window strips from the newer cars to my MPC era cars. The newer "made in China" aluminum cars use the same molds as the MPC era ones, so the window sleeves are identical. Apply the glue and let it sit for 4 hours or more (or whatever the instructions say - some may say overnight) and it solidifies a bit, so when you slide the window strips back in the glue doesn't smear and mess up the part of the window that will be exposed. Press along the top and bottom of the strips with your fingers to finish the bond.