Howdy doo. Since you're that far in might as well perform an air test. Get the fitting from Amazon (about 10 bucks), fab up a cheap hose using parts from Harbor Freight and plug into the IPR port. Use around 130-150 psi pressure if your compressor can handle it. I just did this myself a few days ago (total cost about $30.00). There's tons of writeups and some videos on this. If your pump is bad the system won't hold pressure on it's own and you should hear gurgling sounds in the oil filter housing. This test is the best way to rule out the HPOP.
EDIT: just read that you live in an apartment complex but all you need is a small air compressor. If you were able to tear into the truck this much you should be allowed to run an air test hopefully.

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EDIT: just read that you live in an apartment complex but all you need is a small air compressor. If you were able to tear into the truck this much you should be allowed to run an air test hopefully.