the y8 is obd2 and the z6 is obd1. so it would be a little different of an affair if you swap the y8 in your 5th gen because of the fact that it is obd2 with the different sensors unless you get the WHOLE car or something and you have everything you need then you can do the swap, only problem is that your car would be obd2 now and you would need an obd2 ecu from a 6th gen EX. the downside to obd2 is that it isnt as tuneable as obd1 thats why you see a lot of people changing to obd1 when they swap engines.