The day cab Freightliner is an easy kitbash: Cut the back off, clear of the window casting, and glue a new back on. although you may have to add some styrene to the frame to hold the shortened cab in place. I've done that. The bigger issue is that the fuel tanks stick out too far, which requires cutting the frame, and remounting the tanks. The problem is that the frame is too wide, but simply narrowing the part between the wheels and the cab isn't difficult.
The "suicide cab" Kenworth is even easier: Take the sleeper off! I've converted a bunch to straight-top sleepers by cutting the tops off and putting new roofs on them, so that isn't hard either.
On both, removing the rear fenders helps "Americanize" them, but I have seen a few tractors with such fenders. Most were pulling tanks, but a few were in general service. Apparently they were available as an option in North America.
These definitely show their age, but they're really not bad models, especially if you can find them on sale.
