one more observation:
Halifax got me thinking, my tbar is a 15, so 30* at the crank. I wanted 16* at the crank, so roughly half the slot. The picture below has the 16* slots under the tbar. The inside of both pieces are flush, the fbo plate should restrict the travel by more than it does.
my micrometer needs a new battery, so I wasn't able to get slot readings last night
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