wolfonahunt The choice is yours. You can use the pushin plugs as long as you stake them into the holes. Drilling, tapping and maken sure you get all the metal shaving takes more time. You also have to make sure you don't screw the threaded plugs in too deep or they may cut down or off the
oil supply to other parts of the motor. Make sure you use a sealer on either way. Very thin coating is needed. You will need a deep tap for one of the holes. Threaded when done right is better as long as the sealer holds the plug from spinning. The standard way of pushin plugs has worked for better than 40 years. If you are running a HVHP
oil pump, I would go to threads.
IMO Rick L.