Dynamic block with equally divided array?

Hi, I'm trying to create a Dynamic Block of an 3/4" x 3/4" aluminium angle with holes:

Depending on the length the number of holes will vary.

The distance between each holes need to be somewhere between 8" and a maximum of 12".

The holes must be centered and start from 1 1/2" up to 2" from each ends.

Each distance must be not more precise then 1/16" (no rounded off dimensions)

I'd like to simply drag the handle of the linear parameters (No lookup or visibility for 2 hole, 3 holes, 4 holes etc.)

Thanks

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