While building on a trailer for the 42078 Mack I found it (too) tedious to use the big truck to test the set up. 
Therefore I decided to build a small / handy tractor truck. From the chassis that I have built (see folder above) I selected the 42024 chassis as base because it had (almost) same track gauge.
Pictures show my preliminary version with some red intermediate 3L pins and without decorations (lights, mirrors, ..) installed.
Fifth wheel is a copy of the one from 42078.

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