[Luke]

It is very easy to replace.

-Remove the 4 bolts where the driveshaft meets the differential
-Slide the driveshaft out of the transmission
-Pull the old seal using a seal puller or suitable tool
-Tap the new seal in (I believe you should lubricate the inside of the seal w/ silicone lube, not sure about that one)
-Install driveshaft in reverse order.