I assume this is a manual box? I would take it apart regardless, since there isn't much inside and hard to mess up. If originally a slant, it has a simple bushing on the output shaft instead of needle bearings. I took mine apart recently and replaced only the seals. See my post. Most important is to re-pack the grease, since probably dry inside. Seach also for a moparts post that gives factory PN's, though most no longer available. The input and output shaft seals are the same as in a power box (less dust shield), if you get stuck. See rockauto.
