[SAR_Squid79]

The axle code for your rig can be found on the manufacture's sticker located on the driver's side door jamb as follows:

First digit:

A = 7.5" ring gear
B = 8" ring gear

Next two digits:

01 = 3:42
02 = 3:58
03 = 4:10
04 = 4:56
05 = 3:15
06 = 3:91
07 = 4.30

Last digit:

A = 2 Pinion, Open
B = 4 Pinion, Open
C = 2 Pinion OEM Limited Slip

Some '98-00 models have shown a BO code of "???" on the door plate; so far this turns out to be a 3.91 gear ratio, at least for the 5sp. RZN171L-CRPDKAB with factory 31s/265s should be 4.56 with the AT.