Thank you for the pictures. That is a clean installation.
I have a Spicer 5831 with the same ratios that I dream of installing in my F-2. I am concerned about the height. I looks like you were able to tuck the auxiliary up under the cab very nicely. I hadn't thought about doing a low mount on the front, but it makes sense when I see it. It looks like it gives you a little more clearance for the shift rods.