PM or email me for a few tips and techniques on the timing gear change. The cam does not need to be removed. Back in the dark ages a timing gear change was about a 3-4 hour job for a good flat rate mechanic. It's not as simple as it sounds, but there are a few sneaky tricks that make it a lot easier and safer. I like to drill and tap the camshaft snout so a harmonic balancer installer can be used to press the new gear on- - - -it beats heating and/or hammering the new gear. You can check for bent valves before you do the gear change- - - -just back off the valve adjustments so both valves are closed and put a little air pressure into the spark plug holes. If you get a gush of air from the carburetor there's a bent intake on that cylinder. It's impossible to bend an exhaust valve by getting the cam out of time.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!