I would be more concerned that the back of your boat would be extending well beyond the end of the trailer and this is where all the engine weight is. The result is the tongue of the trailer wanting to tip up. Can you just have the marine pull it and block it?
1997 Silverton 362, 7.4 Crusaders
1997 2400 SCR, 5.7 Vortec / Bravo 2