Leak from output shaft on T-case - hard to replace?

Took the SRX on a 5-hr trip to Indiana this weekend, and after parking noticed a few drops of oil on the driveway.  Slid under the car and saw the leak was coming from the front output shaft seal on the transfer case.  It''s a small leak, but I''m sure the T-case doesn''t hold THAT much oil so I should address it promptly.  Has anybody else encountered this leak and if so, what is involved in the replacement?  I assume it''s not as simple as just pulling out the front input shaft, pulling the seal, hammering in a new seal, and then re-filling the oil?  Is it gonna involve dropping the t-case?