I think maybe a call back to GM performance telling them no one would do a "EVA" would have been interesting. If they were the coordinating office, you needed to get step by step direction. When what they told you did not work, call back and so on. This is how you handle a situation like that. Find out who controls the situation and follow instructions and report dealers who don't cooperate immediately . The motor being in an "old car" would have no bearing. Did you ask them "What does that have to do with it?" The engine does NOT know it is in an old car. Did you ask where it says in writing what years and make and models of vehicles are covered to put it into and which are not? Well, too late now. Should have posted again after you said "it went away" and gotten advice/suggestions/experiences at that time before tearing into it. Never touch a warranted anything. Parts for the engines are made all over the world and assembled in places like Mexico. The balancing and machine work was most likely done in U.S. or Canada. If GM did it in Mexico, it would be under supervision by GM personnel with the best equipment available. If it was under warranty and vibrated and you did not screw it up with wrong parts, they would have replaced it/fixed it. It's GM for Gods sake. The dealers want to make the money if the install is legit, old car or not. People put them in model T's, is that old enough?
