they do have the same lug pattern and as for too much fuel you use a fuel pressure guage to check the pressure at the schrader valve by the fuel rail. It should be between 30 and 40 psi. For your high idle it almost sounds like a really bad vacuum leak. Check for hoses you may have forgotten to connect and after that start spraying carb cleaner around the vacuum lines if the engine sputters you have a leak there. The engine is supposed to idle high at first, around 1300rpm or so. After a couple minutes its supposed to come back down to 700-800 rpm
