I have my dad's 1982 280ZX, 129K miles. A metal part and piece of bolt fell off the back of the car, I brought it in to a car shop, they tell me it is the "exhaust manifold head and stud signaling a serious engine problem", that it is leaking through the gasket causing a putt putt sound, they said the only choice for repair is to remove exhaust manifold and intake manifold, drill out the old bolt, if that works....if it doesn't work, then they need to take the cylinder head off. they estimated minimum $1,000 just to determine what to do. PLEASE: I need advice. Do i repair the car? How much money do i put into the car when it is 1982 and 129K miles? Do i try to sell it in its current condition? THOUGHTS?????