this is a pretty straight forward task. you will be taking one side of both drivelines off, so make sure your on a level parking surface, chocks the wheels, and set e brake if you have one. mark the drive shafts before removing from transfer case, drain fluids from t case and transmission. I use a 2x4 or equivalent to support transmission from inside the cab, as the only support for transmission and t case is the mount on the t case, you could use a jackstand from the bottom, but supporting from inside give you a little more room under the truck, remove tcase bolts that attach it to transmission. at this point you can place floor jack under crossmember, remove 4 bolts that hold crossmember to frame, and slide rearward to disconnect from transmission, then slowly lower down. being your first time I would highly suggest a friend to help, one guy working floor jack, other guy supporting t case when coming down. once t case is removed, you be able to see the output seal on transmission. I would highly recommend marlin crawler output seal. once new seal is in, lightly grease seal, make sure to use caution when putting t case back into transmission, as not to harm new seal. oh, and don't forget to remove t case shifter before removing t case, torque all bolts to spec
