I have an 03 Land Rover Discovery se7 which I might have blown the head gaskets or the sleeves.. I wanted to know if I can switch out the engine with a 2001 Discovery or a 2004 Discovery or a 1996 Range Rover 4.0 SE or can I switch the transmission over from a 96 Range Rover SE to the 2004 disco2. Are any of these parts interchangeable and will I have to change anything on them. I'm trying to get my 03 disco2 up and running but I also have access to an 04 which stated that the engine might be good. I have to go and do some compression test an oil pressure test on it sometime this week before I decide what to do that I'm trying to get this figured out as soon as possible because I live in Pennsylvania and it already started snowing...thanks for all the help