Dont know if you have already found ou what gears you have but I thought most 3/4 and 1ton fords came with 4.10 or 4.11 gears the 1/2 to front axle should have like 3.50 or 3.73 not exactly sure kind of a guess.  But to know your sure pull your diff covers and count the teeth on your ring gear and on your pinion the divide both those numbers by each other and thats your gear ratio    exmp. Your gear set said 45:11  45/11=4.09  rounded to the nearest tenth is 4.10.  There now  I need to go let my brain cool down.