98 Taurus 24V oil sender unit

My 98 Taurus 24-valve 3.0l has been leaking engine oil for several months.  My wife took it Ford today and the Mechanic said oil sender unit leaking-repair $96; Pan Gasket-repair $200; and Front Cover gasket-$1500.  The engine must removed to get off the front cover.
So my question today is Where is the oil Sending Unit?
Do I have to remove the exhaust system?
Can I replace just the Pan gasket?
The Ford mechanic said that both gaskets have to be replaced at the same time to be effective.
My car only has 84,000 miles and I purchased brand new.
ANY ADVICE?
 
Thanks
 

Did they do a dye test on it to confim or just look at all the oil and see dollar signs?  The oil pressure sending unit is located just above the oil filter on the left hand side of the block.  Relace it and then wash the engine down at a car wash and watch for more leaks. If the sending unit is leaking, you will have oil on the pan and possibly front cover.  Just my .02 worth.

Thanks for your reply.  I see the sucker.  Now to get it out. 
Another oil sender unit from CarQuest was $8. Pan Gasket $36.
Taking the exhaust off will be difficult.  One of the back exhaust nuts is buried; covered by a heat shield and a pipe to the tansaxle/transmission.
Any suggestions?