Re: drain fuel tank
When I have needed to drain an onboard fuel tank I have:
1. Disconnected the fuel line from the engine.
2. Removed the connector at the engine end.
3. Stuck the naked end of the fuel line in a vessel (on the ground beside boat) to receive the fuel.
4. Pumped the primer bulb to get syphon action started.
That will get about as much as you can get out. Add a few ounces of HEET to get any water left over. It might also help to add a gallon or so of fresh fuel to mix with any left over crud and drain that, too.