We just bought a 35 foot motorsailer with world cruzin in mind. I plan on a small compressor and two LP tanks to save room. The easy way to do it is dive from the dink. A 10-12 foot inflatabe makes a great dive platform tied aganst the mother ship or off on it's own. To dive from the big boat you just need a trailer line and a couple of tag lines to tie your gear off on in the water, climb up the ladder the lift your BCD up.