Two more thoughts Don. I don't know if you intend to put the vents back in the doors or not. It might be worth doing a mock up with and without, stepping well back for a perspective view, and then deciding. Having the vertical bar in there would change the appearance of the chop, and the visual shape of the cab turret proportions. My mind's eye can't tell at this point which would be more complimentary. With the Studey fins, and the likely elongated image they'd contribute to, I'm inclined to not do the vent because the stretched opening would play to that look. But it couldn't hurt to check out both ways.

Also, if you were inclined, there is now a one piece windshield available for this cab, thus eliminating any parting line.