Drag to orbit. The car is shown fully assembled — cabin seated in its pocket, all four wheels on their axles — standing on its wheels. The engraved plate, if any, is on the rear bumper.
How the wheels spin. Each of the four stub axles is printed as part of the chassis itself — not a separate rod — and ends in a small rounded ball tip. The wheel's bore is cut deliberately looser than the axle along its whole length, so it floats clear of the shaft and turns freely instead of gripping it. The ball tip at the very end is the one spot that's slightly larger than the bore: push the wheel on and it pops past the tip, and from then on the tip is a permanent stop that keeps the wheel from sliding back off. It's a real rotating joint, not a friction fit — the only one in this line so far. The wheels don't steer; all four are identical.
How the cabin stays on. The cabin is a separate wedge — flat base, narrower flat roof, sloped windshield and rear glass — with a shallow rectangular plug on its underside. The chassis has a matching pocket cut into its top, and the plug carries a thin raised rib on its front and back faces that presses into the pocket walls as it seats. It's the exact same tenon-and-rib joint our House Kit's walls already use, printed and proven, reused here so the cabin resists being knocked off a shelf without any glue.
What prints. Three files, six printed parts: the body, the cabin, and one wheel that you print four times. The axles are set low enough on the chassis that, once the wheels are on, the car stands on them with real clearance under the belly — it rolls on its wheels, not on its underside.