I purchased an undecorated caboose (Atlas) that I'm going to paint in my road's colors. I disassembled everything with no problems, but I'm not sure how to remove the window glazing. It's glued in place, and there are also a couple of alignment tabs. My first instinct was to use an X-acto knife and attempt to just pry it up...but I don't want to crack the glazing. Any suggestions for how to safely remove them?