By the way, a compression test really tells you nothing. Something really has to be wrong to show up on a compression test. My engine still had ok compression, but it was obvious the motor was sick. A leak down test is what is in order. A leak down when performed by a competent mechanic won't lie. In fact it'll put the enigine under a magnafying glass and make some insignificant things seem terminal. The interpretation of the test is just as critical as the test it's self.

Oil change records is they key.
7.4 chevys are bullet proof as long as they are left stock.