There are a couple other things that caught my eye too, having owned a 78 that my parents bought new; were the rear window sliders available in 78? Also, I've never seen those type side mirrors or the chrome gauge bezel on a 78 either. It has always been the little square mirrors and either wood style or black plastic bezel.
yea i had them on my first new blazer, a 76 or 77,

ah when i wake up I will remember, anyway I thought it looked more "loaded" with them. Now I lean towards the cleaner look (and less gasket problems) of the flat glass.
He says it was never driven with the top of, but why did they put the hangers on the roof then?

That was done by someone who takes it off often.