ajcajc

Is it common for the rear main seal, crank seal, & exhaust manifold gasket to be replaces in a 92 with 27,000 miles?

PatternDayTrader

No.
It is common for folks to mistake an intake manifold oil leak, or an oil filter adaptor oil leak, for something much more expensive, such as a rear main seal.
I don't think the exhaust manifold even has a gasket unless you mean at the exhaust pipe and not at the head.