Step away from the guitar, and put down the tools!
"How far away from the humbucker" is not a question to ask when placing a bridge.
The bridge position is determined by the scale length.
No offense here, but if that's foreign to you, then some reading is on order.
Well, oiling a fretboard (Rosewood, Ebony, etc), doesn't really fall in the category of "finishing".
Those woods are naturally oily, but can dry up. By wiping them down with some oil, you're simply bringing them back to their glory....