A Fraggle is knee-high to an average 6-foot human (about 2 feet, roughly the size of a lawn garden gnome) and Doozers are not even waist height to a Fraggle (making them but a couple of inches tall). Given those parameters, it should stand to reason that the huge Gorgs should be twice the height of your average human as far as the show is concerned. But, in real-life, since the Gorgs are performed by two performers - one inside the giant costume skilled in mime and the actual Muppeteer off-set controlling the facial expressions by way of radio control devices worn over the hand, much like a conventional puppet - they're probably only physically wider than an average human due to the sheer size of the characters.
Oh dear god, my sides! So many memories. Also, I have the mental image of the Sequential gang dancing with the Fraggles. Pip doin the Irish shuffle, the Denizens performing a miniature Thriller, Kat n Art are doin the disco and the Squirrels are doin one of those anime happy dances. WOOOOORRRRDSSS!!