It's not hard to do, but you need to take the tranny and flywheel off, then unbolt the seal carrier, knock out the old seal, put in the new, gasket-sealer the carrier back up and bolt it in. Bolt back up the flywheel and tranny and call it a day. [with all this work though, it's a good time to get a new clutch and have the flywheel surfaced or replaced with a lighter weight one.]