Hi I do not know much about cars but love my 1977 Buick Skylark. I have now however been told that he needs an engine rebuild or a new engine, and I'm wondering weather I can justify spending the money on him. He has done 87,000 miles, his body work is in mint condition and the interior is good. The mechanic says his transmission and rear bearings look good and does not see any other problems other than the engine. I have no idea how much he is worth and wondered if anyone could tell me roughl