i got a five speed box of a mate who said it came out of an astra it fits the engine no probs but it will not engage the gears i have set it up as per haynes but no joy i have seen on here that a certain type is a cow to fit how do i know which is mine, its going on a 1.2 for insurance reasons also does the selector of a 4 speed fit a five they look the same as the one on the five was seized if that helps. cheers in advance??