Hi folks - just joined to reply to gevans12 post to say I just did this same thing. After building the 8043B dozer I was looking for a truck and trailer combo to haul it.
I started with the 9397 for the truck with only minor mods. To shorten the chassis, I moved the "fuel tanks" under the cab doors, pulled the rear wheels in front of the geared wheel set, then removed the rear box girder (for lack of a better term). I also pulled out the battery pack, all the gears and supports for the loading arm and the log retention beams.
I built a "lowboy" trailer freehand based on an Eager Beaver design. However, it needs serious reworking as it's not strong enough to hold the 8043B without considerable flexing in the frame.
Here's a small photo of the set up.