Hi Joe!
Excellent and common question.
I see from google maps you are posting about a one-way under 180 miles jaunt 'a few times a year'. The new Ford 150 is a remarkable truck by all accounts. The tow rating is marginal for a cruise-mode TC255.
http://www.ford.com/trucks/f150/specifications/towing/
I am the only TC255 owner to put the damn thing on a truck scale and post about it... I got 11, 800# with 3/4 gas and 1/2 water, empty holding tank and your 'cruise mode' will vary...a LOT!
Full Gas alone weighs 900# in this mother, and your truck bed loading, and passengers, affects your overall tow rating a lot. Perhaps you will want to pump out 150 gallons of gas from the boat to lower your towed wgt. Perhaps you will not want to do that. I sure don't want to.
I would suggest you be honest with yourself and your loved ones you are hauling with this boat and put it on a scale in YOUR Westpoint Cruise Mode with Typical Gas load. If that added to All The Stuff you would put in the F150 pickup bed + the ACTUAL TC255 TOWED WGT is within Ford published limits, then you should go with the F150 3.5 Eco-Boost.
Unfortunately, I give you 95% odds you will be exceeding those safe limits. What you want to do about that is up to you. My impression of the best compromise is to buy an older (but not that much older) HD2500 diesel truck/SUV and be ready to safely tow anywhere in the country (Deisel FUEL here is $1.56 today). It can still be your commuter truck, and even with the diesel fuel, cheaper in the long run than a new F150. Run the math. It's a bear to park at WalMart, but, it tows that rig a LOT better...so much better you will never go back.
As far as 'what you can get away with', I just plain don't advise going there...ever. Not in your towed boy toys, not in your finances, not in your professional life, not in your boat battery bank capacity, and sure as hell not in your love life.
All that said, you should make your own decisions.
Cheers!
John