Old TP callout

[[Pe...]]

The 1970's are calling.

Is this just a TP Ø.020?  I dont have any datums, but I do have some basic locations of these hole locations.

[[He...]]

If there is nothing else controlling the location of these holes I would assume the design intent is that the datums is the features that the basic values originate from. If there are other dimensions controlling the location I would assume that this is like the lower section of a composite true position. Just these two holes relative each other.

I would ask the designer but he is probably retired or dead by now.

[[Mi...]]

I believe you are correct

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. If the basic dimensions are to planar surfaces, or to other features from planar surfaces, they're asking for TP Ø.020 to the referenced surfaces. Depending on what standard is referenced on the print you'd also get a modifier on those holes too.