a few questions, im developing an oil leak where theres a small puddle resting in the lower motor mount. i believe its coming from behind the crank pulley when i had to take it out to replace my CPS sensor. i think the gasket/seal thats wrapped around the crankshaft is broken and causing my oil leak.

what's that gasket/seal called? heres a pic for more clarification:



with crankshaft:


is it called the front main seal as found from zzp's website?



lastly how hard is it to replace the gasket/seal? do i need to take the front cover gasket off or just pull the gasket/seal out and swap in the new one(whatever its called)?

thanks in advance!!! i want this leak gone