What year xj ya got? The earlier model HO moters have a two piece seal. I'm not sure about the renix. But in any case...You need to drop your oil pan, loosen the bearing caps on the back end of the crank, pull out the old seal, goop up the new one with vaseline and put it back. I did mine last summer, and it was a lot easier than Ithought it would be. 10 months later and still no leak.