rear main seal leak on 1998 Oldsmobile Silhouette

What is the cost to fix a rear main seal leak?

Asked by for the 1998 Oldsmobile Silhouette
Basically you have to remove the Engine cradle and separate the engine from the transmission. this is going to be a 10-15 hour operation. the part is only about $20.
will bars leak rear seal repair stop me from losing oil only when i am in drive dont leak when onlt idling or in park