I havent yanked the stock shortblock yet, but looking at the Ford Racing 351w swap pan, there is no spot for it so i was wondering how it actually worked.
Don't know how it functions exactly, but I did remove mine and used the location for my electric oil temp guage.
I check my oil every time I fill up, so I didn't think it was important. Not to mention it usually won't come on until after the car is parked and restarted with low oil. I think it comes on between 3 and 4 quarts, not 100% sure.
Sorry I don't have your answer exactly, but just though I would share my use of the location........
well, if its anything like the one in our coolant reserviors, I believe it uses the fluid to make a closed circuit. if fluid is below the unit, there's no continuity, it's an open circuit, thus turning on the light on your dash.
I'm pretty sure you can tap a hole somewhere on the pan. hope this help