Hello, thanks in advance for any answers. I have a 1989 outboard that bit the dust last year when an oil line busted going down the lake. I'm looking at a 1984 (with low hours) outboard that only needs a lower unit. Both are Mariner 115 hp. Would my good lower unit from the 89 fit the good 84 motor? If so, how much should the labor be to put these two together. Thanks again...