Oil Pan Problems
 

I just had my 88 5.0 engine rebuilt and when I got it back there was a gauge broken off sticking out of the side of my oil pan. I don't know what the function of this gauge is or even what it's connected to, but I have to buy a new one, now that it's broken. I read through my Chilton's manual, and the only thing I think it could be is a pick-up tube (whatever that is). (By the way the oil pan is a double-sump oil pan, if that matters). If anyone knows what the gauge is for (and what it's called), please let me know, thanks a lot, I appreciate everyone's help!

Sounds to me like that might be the low oil sensor. Lets you know when you are a quart low.

Mystery gauge
 

Yep. It's gotta be the oil level indicator sensor that activates the 'Check Oil' light. Available at Ford for about $30. - 35. as I recall. Call around the parts places, it may be available - and cheaper - elsewhere.