My personal opinion is that you will not have much luck locating a 327 in a salvage yard, considering they have been out of production for almost 30 years. You will have better chances of locating one by either going to EBay, or swap meets. There is not much any one can tell you about what to look out for, unless you know the history of the engine, or the owner. I happen to know where two complete 327's are and I could see if the individual would be interested in selling one if you wish. Be aware though, they can bring a premium price.