Good morning! I did a search for the referenced topic and found on a Tundra that the width of the rear is approximately 46", but I’m also looking for the height.
My truck is a Ram 2500 (GFC delivery scheduled July 22) so I’d also prefer to know the specific dimensions (WxH) for my platform. Figured I’d try here before bugging corporate. Thanks for any help with this! 
I don’t have a 2500, but the box is the same size on the 1500’s. If someone else doesn’t beat me to it, I’ll get a measurement when I get home. So unless GFC has changed their window size you should be good to go.
Are you making coverings? Personally I just went with a rectangle 
I’m actually having a vinyl decal made up. I’m over anxious and impatient and am getting all the cool things ordered pre-delivery. 
Here you go. This is measured with a 1” tape flush on the inside of the gasket (if that makes sense 
). I get the excitement, it’s totally worth it!
Sweet! Thanks so much!
If you just need the measurements for the rear window-it’s tapered so at it’s widest length wise it’s 44 1/2 “ and 12 1/4” high. (That’s solely the glass being measured).
Thanks. That was cut using the widest dimensions provided on the glass and I’ll just trim to fit during install. 
