Composite Tolerance

I am having trouble understanding composite tolerance, especially when it comes to a bolt hole pattern like this. I am wondering how you would dimension these true positions. Here's my idea using legacy dimensioning:

Level and translate to A, rotate to B, and report the position of 1 hole (any hole?...lets say the 12'O'Clock hole) and give it a .001 tolerance. Then, would I stay leveled to A&B, translate to the hole that I just reported on (12'O'Clock hole), and report the positions of the rest of the holes with a .0005 tolerance?

Thanks so much...I prefer to use legacy...

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kingsld1 over 2 years ago

Also, the lower frame should only have 1 datum. As written, the FCF is basically just repeating itself, with a tighter tolerance on the lower frame.
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kingsld1 over 2 years ago in reply to kingsld1

Respectfully disagree. In my 40 plus years of GD&T, I've never seen a composite position callout that repeated all of the datums in the lower frame. If the upper and lower DRF's are exactly the same, then how does the pattern float? The lower frame always drops at least the last Datum from the upper frame.
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kingsld1 over 2 years ago in reply to kingsld1

Respectfully disagree. In my 40 plus years of GD&T, I've never seen a composite position callout that repeated all of the datums in the lower frame. If the upper and lower DRF's are exactly the same, then how does the pattern float? The lower frame always drops at least the last Datum from the upper frame.
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