Could just be the angle of the pic, but it already looks like you have little tongue to work with. The characteristics of your rig, especially in reverse, by moving the bow stop even closer to your tow vehicle will take some getting used to. Take care not to get yourself in a jack-knife situation. In fact, I might actually opt to adjust the axles instead of the bow stop if it were me.
Also, the Pilot's wheelbase is probably borderline for an 18' boat. General rule of thumb is 110" of wheelbase for a 20' trailer and add 4" for every additional foot of trailer. Pilot is right at 110" and your boat as it sits on the trailer should be about 20-22'. Of course this doesn't account for any physics, road conditions or when a trucker passes you at highway speeds so YMMV.