size of rear window

[Cartman]

would love to help, but mines currently buryd under 2 feet of snow.... instead of in the garage it was suposed to be in.. snow cought me off guard

 

[zinc2000]

Sorry cannot access back of mine under its cover in the garage for accuracy but approx if it helps is...

Top/bottom at centre...26.5 inches

Side/side at widest....53/54 inches

Sorry cannot be more accurate for you hope it helps

 

[YOG]

Assuming you're talking about the rear hatch and the actual glass, not the aperture in the hatch:

Glass, top to bottom at centre - 66.7cm/26¼ inches (approx.).
Glass, side to side at widest - 126.7cm/49⅞ inches (approx.), following curve of glass.