Hello, would anyone happen to know if I can replace a Mercruiser 120 HP (chevy 153 c.u.) engine with a 1993 Mercruiser 3.0 (181 c.u.) in my 1968 Sea Ray SRV170? I'm not sure if the engine mounts are the same or if the engine would line up properly with the shaft to the outdrive. Thank you for any suggestions!