when you go to a place like that with 15 or 20 grand you might as well write sucker on your forehead. The mechanic is not sure what parts he put on? What kind of shit is that. How hard is it to make a list and install what's on the list. I think you have to try to screw somebody over that bad and they obviously thought they could get it past you. From personal experience whenever you put that kind of faith and money in somebody and expect them to take care of everything without supervision you will get burned often if not every time. Ususally you have to watch their every move. Unless it is somebody special like maybe Greg Dupree (by rep, never met him). Sorry for your situation and good luck in the future.
L.A.N.C.E.: Lifeform Assembled for Nocturnal Calculation and Exploration "What a beautiful life this would be; if I could just get it right" Vallejo