That seal will be very difficult to replace without pulling the case. The housing for the front output shaft also retains the shift rails, and they can be a real PITA to put back in the bearing retainer due to the little shift detent balls and springs. It is no big deal to pull that case, you can have it out in under and hour, all you need to do is unhook the driveshafts, disconnect the shifter, unplug the 4wd light and remove it. Of course, you need to remove the skid plate and support the engine with a jack. When you do replace that seal you may as well replace the 2 shift rail seals also. Almost forgot, don't forget the t-case input shaft seal that is in the back of the tranny. You should always use a new one, just pop it out with a screwdriver and put a new one in.
ORC Land Use Section Editor
Vice-Pres. Rock Garden 4 Wheelers, Farmington, NM