My '67 7500 had a 5-Speed Clark, but just to make it a little more clear, I got the PTO with the truck deal (already out). I don't believe it would had fit the Clark trans, but I never tried it. With the original plans to make a flatbed dump out of it, I put a box body on it instead and sold it soon after.
I do have a '68 and a '72 C-30 though. I believe they both have 465 4-Speeds. One has a PTO on it but I believe it's an aftermarket. Once I restore the truck, I'll find out for sure.
In the meantime, I'll try again on pictures of my Spicer. As time allows, lol.
Appreciate the replies so far.