Tooling hole to conductor pattern registration specification

Hi all,

We have an assembly which features non-plated tooling holes used to align the board in a bed of nails style test fixture. This assembly is rather small, and as such, the test points are pretty small as well. We have found that some variation exists from board to board associated with test point location with respect to the tooling holes. This has caused some of the units to false fail during testing as a result of the bed of nail fixture pins not aligning properly with the small test points. I was curious if anyone knew the industry bare board spec that addresses the requirements for tooling hole to conductor pattern registration accuracy.

Thanks in advance!

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