Hi Les!
You did a great job on these two Opel Blitz. They are those Italeri kits, right? I have them here also, the fueler is already built (but not as good as yours), the other one follows next year.
But why did you change the cabins? As far as I know the fuel truck (Kfz 385) was only built with the canvas cabin. And the 3 tons cargo truck (Kfz 305) was built by Opel with the metal cabin. Daimler-Benz has built the Opel Blitz in licence with a different cabin, the so called "Einheits-Fahrerhaus", which was never used by Opel.
Happy modelling!
Torsten