If the slide doesn't float up and down, no problem. Our Harley brethren typically bore to 1/8"; some say the larger hole induces slide flutter--if not, WHAT? YOU worry?
Finish/material remains of no consequence with shimming washer; all you need is about 25/1000" thickness, IIRC.
And, once your 22-cent modification is complete, you can attack the World Land Speed Record, feeling pity for the poor souls who ride their stock KLR650s in blissful ignorance . . .
FULL DISCLOSURE: I performed the 22-cent mod on my own Generation 1.