Take care ... Corolla starters can be too big for the standard conversion kit (mine was) - although I believe it is possible to get the larger parts machined - hopefully Dave could confirm. Also, note that starters from the likes of Suburu and Rover may look similar but will turn the wrong way and may have the wrong number of teeth. As stated above, you don't actually need to do any machining with the Isuzu Trooper motor and neither does it require a conversion kit - so if you can find one in a scrappy it's probably the best bet for 4 cyl cars.