Frosty, thats good advice re the engineers blue (which I dont have) or pen ink (which I do.)
the other option is to file the locating tabs off the switchblocks entirely, and then use a thin strip of rubber* as a washer to hold the block to the bar. I think I read that tip on KB and its worked a charm for me. no issues with switchblocks spinning, and no requirement to drill a hole in a brand new near $150 Renthal (which if you read the instructions say "Do not use if there is a hole in these bars, do not drill them, discard if bent yada yada")
this sounds like a minor bend in the stock steel bars tho
*bicycle inner tube fTW: I have an endless supply of them.
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