You can get the kit from Marlin.

This is not for the mechanical novice. Each end of mine took about 6 hours...but that's on an axle that nobody have ever been in for 21 years....Half of that time was cleaning.

Anyhow, tools...snap ring pliers, socket sets ( everything from 10mil to 20, plus a 54 (or 53) for the spindle nuts. Torque wrench ( very important) gear oil, CV grease, bearing grease, rags ( lots ).....if you are replacing bearings you will need a hammer and a BRASS drift, NOT steel. Jacks, jack stands, containers for parts...

Point is, if you are going in, you gotta do it right. At the very least get a kit with all the seals and gaskets.