Slant 6 oil pressure woes…

Because even though I just put 5qts into it, it was still a good bit low, also, I have a high capacity filter on it.
What's the filter part number? I run a Motorcraft FL299, which IS a high capacity filter. It's a 2 quart filter, whereas the stock one is a one quart filter. Although I do run six quarts, I'd never put seven in it. That'd certainly risk hitting the crankshaft.