Hi everyone. I have a 1988 Celebrity with a 200hp 5.0 alfaone I/O. I messed up the drive unit last year. My thoughts are no oil in lower end. Anyway, I have decided to simply buy one from the Iboats web page. My only questions are, How do I know what gear ratio and tooth? (or what else I need to know before having it shipped? ) as there are several to choose from. Help here would be very helpful and even more appreciated. Also, can someone explain if faster/slower ratios can be used in my application? And what the number differences are? Thanx in advance..