ok number one ill itroduce myself.. my name is phil and i own a 93 nissan 140sx s13 hatch 5 speed.. my rear main seal is leaking and i need to know how hard it is to replace and if its worth paying someone 100 bucks with the seal included in that price for it to be replaced.. also i have this weird ratteling noise coming from right near the clutch area... i cant explain the noise i have never heard this coming from a car before.. it does it whether its in gear or not and whether the clutch is held in or not.. thanks in advance for any help..