Lower Unit Swap

[mick_skater]

I have a 2002 115HP Merc outboard (S/N OT586924) that has a messed up lower unit (gear ratio 2.07:1) . I have a spare lower unit (gear ration 2.33:1) that came off of a 2003 Merc outboard (S/N OT746797). I believe both l\u have a 13 1/4" X 15" prop.

Can I use the 2.33:1 l\u on the 115hp? What would be the biggest diffeerence in the performance? Would I need to change the prop?

Thanks in advance.