The big window is rare, which makes it highly desirable to collectors and those that prefer the style. Considering the majority of 60-66 trucks came with the small window cab, it would seem the small window was in fact more popular at least with original owners.
I appreciate that others love the big window, but the sculptured small window back of cab panel is part of the character I love about these trucks. If my truck had been built with a big window, I wouldn’t have bought it.
Years ago I had a 1983 Chevy truck and detested being roasted during the summer months.
Here's an earlier thread on the topic, with an even earlier thread shown on post # 2.
http://67-72chevytrucks.com/vboard/s...g+small+window