Jon, Have a look at the Suzuki 4 strokes. their 90 weighs about what a
merc 60 bigfoot does and uses less fuel. Runs quieter and doesn't
vibrate at all!

I did just look at suzukimarine.com and they say the 90 is 416 lbs. (dry or
rigged?)
That sounds pretty heavy. The merc 60 is 264 dry