"The existence of the flamethrower is evidence that someone, somewhere once said 'I want to set those people over there on fire, but I don't want to have to walk over there to do it.'"
I'm about your same size Lifted and yep the Boxster feels a bit snug but so do most smallish cars I get into (I had a Mustang Cobra before the Porsche, those seats were terrible). I joke that I'm about 3 biscuits away from being too fat for the Boxster but it really isn't the case, as long as you're still limber and not out of shape getting in and out isn't an issue.
i'm 6' / 245lb. i fit ok in the box. i'm all torso, though. my legs are pretty short for my height (30.5" inseam). if my legs were much longer, the boxster would not be very comfortable. the new caymans / boxsters have a little more room.
I am short and fat 5'8" 300#. I really have no problems in my '08 Boxster. It feels plenty roomy but I am used to not fitting well. Also I understand 987s have more interior room than the 986.