oil pressure

It's been a while since I've looked at one but your description suggested that you weren't using the stock oil pressure pressure tap location. Since the pressure tap is downstream of the relief valve at the end of an oil gallery, what I wrote earlier is still true.

The "Ford Stuff" is a oil specification that requires the phosphorus content (the antiwear component of ZDDP) of the oil to be a minimum of 1000 ppm. API CK-4 specifies a maximum phosphorus content of 1200 ppm for 40-grades and higher and 800 ppm for 30-grades if they're also approved for API SN.