I’m with Don. IMHO the maker was “ thinking” about creating a 4wd car with what appears to be a Revell frame; took it all apart to put the motor in and found he didn’t have enough room to properly engage a front crown and then discovered he had lost the guide collar; which he replaced with the crown gear he was planning to useso as to not misplace the guide as well.
He then set it all aside to rethink the project and maybe get a replacement collar. but never returned to it.
Given my predilection for overly complex mechanical slot oddities (e.g. 2 speed rear drives; working differentials, working front/rear suspension w/steering, all of which added zero performance), I venture this might have been done as a DIY effort to copy a Russkit 4WD chassis.