Locker: Jack up the axle and spin one wheel, watch the direction of rotation of the other wheel. If opposite directions, its an open diff (or an unlocked air or electric locker), if the same it is a locker or limited slip of some sort.

Gearing: http://www.4crawler.com/4x4/4R_TechInfo.shtml#RatioDetermination

EFI, a 22RE swap is one good option.

r.c.brown@ieee.org
TruckEditor@tlca.org
Project: 4Crawler
4Crawler OffRoad - 4x4Wire discount code