I would start it in the driveway with dog ears and let run to operating tempatures. May disconnect the gas line and pump (with the primer bulb) some of the gas out of the bottom of the tank before trying to start it. You can do this like a siphon if you can take the connector to the motor off the hose and just have an open end on the line. Better to start it the first ime for the year in the driveway than have problems in the ramp in the cold and the wet and maybe off the trailer etc. etc.

There may be some condensation in the tank that will settle to the bottom. Try not to move the boat around and stir it uo before you use the primer bulb to pull that out of the bottom.