Colonel K,
Whilst I would agree that the RAF's medical branch are rather inflexible when it comes to anthro, once you're in the mob (admittedly the hard bit)you would get strapped in the most restrictive cockpit to see how you physically fit.
I don't doubt that there are 6' 6" USMC AV-8 dudes out there, I'll put money on their thigh bones not being in contact with the seat "cushion". I wouldn't want to try a parachute landing with broken thighs... Even if it's a bitter pill to swallow Matt, it's for a good reason. If you can get in as a helo or multi pilot then awesome, but see above re: inflexibility.
For aircraft like the Sea Harrier I believe it's the sticky outy bits that'll catch your knees.
I would recommend against the Navy unless you like banging your head on pipework. But if they'll let you go flying, that's another matter!
**** (6' 4")