Is this a press fit cam and gear? if it is , get another cam and swap it in and pray the valves didn't meet with mr. piston! you dont have to take the other cam out. you need to manually spin the engine to find the timing marks on BOTH chains and mark them with white or yellow ink. keep rotating(make take a couple dozen times) and check to see that the timing marks on the cam line up and the damper mark lines up. if it is a two piece cam and gear, get a new gear and line it right up! pretty easy to do , just looks way scary!
Hope this helps