I got a lead on a carb but I can't tell which one or size it is. I believe it's a road deamon but i'm not sure. It has the choke tower but the choke has been removed. The only #'s on the carb are on the bottom of the butterfly's. all plates have 1.69 on them. It's a square bore, double pumper. Is there a way to tell if is a 750,850 ? Thanks