Cam Seal replacment help!

So i think my cam seals are leaking(pulley side), could be just my valve cover but anyway, im taking it apart tomorrow and i was wondering if i just undo that one bolt holding on the gear and slip it on that way or do i have to take the whole cam out of the head and do it that way? Any tricks you guys know, timing belt wise or anything that could be useful? Thanks

you dont need to take the cam out of the head. there is a spot on the cam to put a wrench on to hold it while you loosen the bolt holding the gear on. snap on also has a holding tool that holds the gear so you can loosen the bolt but its too big for aftermarket gears cause of the design