West Coast Chopper Nightmare Wcc Jesse James Bike

me and my buddy finally got the engine on his wcc, and doing the rear sprocket was nothing short of a miracle cause of the coaster brake on the hub and the spokes clustered together so tightly. i can't figure out away to get the rear sprocket to come out further from the hub so the chain clears the tire. if i was to space out the hub with washers (or anything else) it will rub against the coaster brake. we can't afford to get a new hub and or relace. does anyone have any knowledge of what to do here on this bike ?

please drop some positive suggestions my way on this im very exhausted from spending almost 16 hours today on this bike and im ready for bed to think more about it myself even tho i cant even see away of doing it.

thanks.