There is no good way to change the gear without pulling the cam.
Make sure you keep the lifters in order.
There are two Philips screws holding the cam in.
I would suggest temporarily putting the pan back on with a couple of screws and install a couple of quarts of oil. Then spin the oil pump and watch the nozzle that lubes the gears to be sure it is getting oil.
I know people badmouth fiber gears but I have never seen one fail that was getting oil.
There is a oil pathway on the back side of the timing plate that is commonly sludge up.
