F60L Cab 12 truck

[Howard]

Gday all,
Shane, my (unrestored) 12 cab F15 has a glass window, as does GT's F60L (and did before restoration), also the remains of a cab 12F60L that I have, has the glass frame.
My old man told me the F15 had glass for a long as he can remember.
Of the two 13 cab fords that I have, one has the sliding covers, and the other seems like it may have had the sliding covers, too.
I know of at least one unrestored 12 cab F60L that has the sliders, too.
As with a lot of things cmp, it seems that there isn't a right and wrong answer. These things were bolted together in a hurry with whatever was available, and then modified in the field probably more than once, and then modified post-service using, again, whatever was available.
From my observations, and point of view, your truck could have originally had either. And you should fit whichever you feel you'd like to have. Don't get too worried about the finer details. It is not a GT falcon, and no body it's going to have a go at you about such details. Just get her on the road and running right, looking presentable, and you will have a lot of fans.
Cheers
H