Hi John,
I’m not sure how an adjustable linkage rod would help with an oblong hole? It seems it would just be loose at a different height. If too much material has been worn away, maybe have the hole welded up and re-drilled. Or drill large enough to get a round hole and sleeve it. I don’t think the adjustment is there for anything else but balancing the two pedals (with consideration to the accel pedal), so only one would be needed. Makes sense to me it would be the center pedal.
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