There shouldn't be much pressure at all in the pan when the engine is running; especially at idle. And if you leave the disp stick ut, the pressure would be real close to zero.
If you put silicone sealant around the studs before installing the pan, that's not likely to be a leak point. It could be, but less likely.
Try this. Clean the front of the engine really well with a good degreaser and plenty of water. Let it sit until everything is completly dry. Especially the valleys near the top of the front cover. After it's dry, sprinkle liberal amounts of corn starch, starting near the distributer, and ending near the pan.
Start the engine and warm it up. When the corn starch starts to darken, that's the
oil oil leak. You might find that it starts at the block/intake seal under the thermostat housing.