What would it take to make a SuperGrafx work in America?
plugging it into wall and your TV. Japan and US both us NTSC standard.
and is there a way to make it play American HuCards?
you can install a region mod same as any other pce system, or use a chopsado made by member chop5 or fork out some cash for a converter but you'll still need to do a minor modification on the pcb for either of those options.