About the timing gears, yes, truck engines (at least 216s) came with fiber gears. In about 1975, I bought a non-running 1950 3100 one-owner pickup. Due to my Dad's wisdom, we pulled off the distributor cap and turned the engine by the fan. The rotor didn't turn. A couple of teeth were gone from the timing gear. I replaced the timing gear and it ran like a champ.
