Outer Limits 4x4 Board

Ive just replaced the stuffed 5spd gearbox in my 90' Sierra, with a box from an 86' Drover. and have a few questions i hope someone can answer.

1) My original box (Don't know if its actually the factory original) had a small breather on top of the box right next to a plugged off hole.
The drover box has no breather, and no hole for a breather, but it does have the plugged off hole too.
Does the box need a breather?

2) There a 4 wires with screw in plugs on the box, the drover box has different electrical connections to my sierra box so i just swapped the reverse light switch over, and snipped off the wires on the other 3 plugs as they were never even plugged since ive had the sierra.
What do the 3 other switches do?

3) Are there any other differences between the 2 boxes (90' Sierra - 86' Drover). Such as ratios? I dont know if its just in my head and im imagining it, but it feels ever so slightly lower geared now - though i have only driven around the block a couple times.

Thanks
Mike

From memory 5th is slighty taller, meaning less RPM for equivalent speed compared to your old box.

Layto....

the breather in the early boxes is nothing more than a moulded pin hole in the small round shift boot.