Are there any easy mods that can be mad to a 454mag EFI to gain a few HP. I currently am spinning a 23mirage plus at 4800 rpm at a top speed of 62mph. Would like to spin a 25p if possible to see over 65.

Go to crockettmarineengines.com. He has a nice upgrade kit for your motor. Shaves and ports the heads, taller cam, better flowing exhaust, reprograms the ECU and plumbs the fuel system all for about $6,500. These mods should spin that 25P prop well over 65.