KB45-08XL 1600kv Brushless Motor

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I'm thinking about getting of those for a future 1/8 conversion. It has a 6mm shaft so what would I do about getting some Mod1 pinions to fit. Would it be better to try and drill out a pinion or file the shaft just enough. If I were to file the shaft how would I do that?

PS
Please don't say save up for a Neu or Medusa I just want to get a budget motor for the future.