Timberman-
The health concerns associated with isocyanates are serious for the user, but also for anyone else who may come into contact with the product (esp. if you are doing the application in an attached garage)

If you do decide to do the job yourself, and don't have access to a supplied-air respirator system as Dan suggested, get a good air-purifying respirator, and an organic vapor cartridge with a P-100 filter. Also, change the filters frequently, and especially if you begin to taste anything that makes you suspicious.

An industrial safety store in your area, such as cascade airgas, sound safety, or a welding supply shop, should be able to set you up.

Even shops with engineering controls in place to vent the workspace still require the applicator to use respiratory protection. This is obviously a little different, as you are only doing one boat, but be careful.

Also, if you have had respiratory problems in the past, you should check with your doctor before you wear the respirator.

Good Luck,
Jeff