The method of check the rear end ratio depend on which rear end is installed.
Does it have a cover or is it a pumpkin type.
If it a cover type, pull the cover off and look at the gear set the ratio or tooth count will be stamped on the ring gear - this will also give you the chance to change the gear oil since it'll come out when you pull the cover. You were planing on changing "all" the fluids before heading out for a long haul right?
