The center hole in an oil filter for our Cummins engines is a regular old pipe thread. I think it's a 1 inch, but I would have to go look. When I prefill a filter, here's what I do.
1. Take the plastic wrap off the business end of the filter, not the whole filter. (I use a Fleetguard filter. No telling what gets into a boxed filter.)
2. Carefully inspect the threaded hole for burrs or leftover loose metal swarf from the threading process. Takes less than a second.
3. Grab a CLEAN piece of steel or plastic pipe of the same thread size and do the same inspection.
4. Thread the pipe in loosely about two turns, no more, as a plug. A plug would also work, if it won't shed plastic or cork or whatever. What I am using most often is a 3/4 inch copper sweat cap fitting. It sets in very nicely.
5. Slowly prefill the filter through the OUTER holes. This is slower, but the oil will enter the center of the filter through the filter media. Because I don't have four hands, I will sometimes do this from a quart bottle or a mostly empty gallon bottle from my last oil change. It also allows me to watch for teensy bits of aluminum seal I might have missed. (Haven't seen any yet.)
6. Wipe off spillage, remove the rest of the plastic wrap.
7. Remove the pipe and check again for pipe swarf.
8. Install normally.
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