So, got in an accident about a month ago with my 02 grand prix gt. problem is, my odometer reads about 180K but i just put a different engine in (an 01 grand prix gt motor with about 110K on it) and they refuse to adjust my appraised value because i don't have a receipt from a certified garage (they say i have to prove the engine isn't from my car some other way). i sent them the title of the vehicle it came out of (was my dad's) and they still are saying the title doesn't prove that the engine is in the vehicle. how the heck am i supposed to prove the engine is in my car to get what it's worth?! i can't find info on whether or not there are engine codes that match to the title i have for the other car. any ideas?! i'm just getting fed up with trying to deal with my insurance