My brother and I did 18 racks of baby backs on a tiny little hibachi style grill.  How?  Rubbed the ribs, ten minutes a side on hot coals to char, double wrapped tight in heavy duty foil, then piled in an oven at 225 degrees for six hours.  Unwrapped, brushed with sauce, then another ten minutes on the grill.  Perfection, on a perfect Los Angeles evening high up in the mountains.