Sounds like frpp cams is what you want. Won't lose much torque and gain horse power. Won't lose any torque and gain more power with a custom tune so it's a win win.
idk if the 3v ones would match up, if you got the 3v heads it might work but then idk if the 3v heads would fit the 2v 5.4l, ive been trying to find a wrecked gt500 and see if i could pull the 32 valve heads and slap em on my 5.4l and cam that but them id need 4 cams insted of 2
Or you could just put the GT500 motor in the F150, put the Kenne Bell SC on it and have Troyer tune it for 626hp at the wheels. '06 GT500 4x4 F-150, built and street proven by Hux Racing Video by HUX Racing - Myspace Video
Be better to jack a motor from a gt500. Better parts in that motor, also 2v to 3v idk about that. Might be cheaper to just do a motor swap.