The measurement between the centerline of the holes on the Carrera part is 1.018-1.020.
Your parts measure 1.010 and 1.012 with my digital calipers. As I said before not a big deal, a little fine tuning and the screws go in perpendicular. It is a similar situation with my 935. The 935 is not my best handling car, after about 50 laps using your adapter and guide the handling has improved. The new pieces allow the guide to sit lower in the slot causing the front end to stay planted. You are probably right about softness of the pieces being the same, it wouldn't effect the way the adapter performed. All in all they are great additions to Carrera cars at a great price. Like I said before I'm kind of picky, but I appreciate the chance to work with you.
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