Rear axle hub seal leaking(?)

The Kit Martin linked above will work. Also available is the "splash protector" which can be damaged when removing the seal in the axle tube ( If you forget its there and haul the seal out with a prybar ) I have run without this when I did damage one once, and had no problems, but it does make putting the axle in without tearing up the seal a lot easier with it in. 
My experience is only with a Non ABS Gen3, but follow the steps in the write up in the wiki and you should be golden. 

www.bigjimny.com/mediawiki/index.php/Rea..._bearing_replacement

​​​​​- Take a photo (many actually) of the drum brake assembly and the locations of the various springs, pins and mechanisms in behind the axle before you take it apart. Saves a lot of headscratching and cursing if you're not familiar with how it all goes together. 
- You will have some brake lines to undo (slave cylinder). I have had success in using a tight fitting rubber bung to the master cylinder to prevent brake fluid from flowing out onto the floor while disconnected (there are other techniques to prevent this). It will still leak a bit so you'll need something to catch that. 
- A long enough piece of heavy pipe is needed for driving the retainer back onto the axle. Use a block of wood or similar on the flange end so you don't knock the studs out. 
- The brake shoes may need replacing if they're soaked with gear oil. I have successfully reused some that were nearly brand new and didnt want to throw away by gently heating the inside with a small propane torch and "melting" the oil/grease out of them. If in doubt, replace them, if you just use brake cleaner on the outside, the oil will cook out when the drums / shoes heat up under braking anyway and they'll be next to useless. 
- As mentioned above it may be a good idea to remove the ABS sensor before removing the axle.

Sorry its a bit long winded. It's not exactly a difficult job to do (with the right tools) but can be a real PITA sometimes.