Disconnect the coil, remove the #1 plug. Crank the engine over while holding your finger or thumb over the plug hole. When it comes up on compression you will feel the pressure come out of the hole. Look at the balancer, the timing mark should be very close to TDC. Use a socket and breaker bar to turn the engine to about 10 degrees BTC. Pull the dist cap and see where the rotor is pointing. Check the plug wires are correctly routed, big block distributors turn counterclockwise, if I recall correctly.
Now, put the dist cap back on, hook up the coil, and turn the ignition on to the run position but dont crank. Replace the plug & hook up a timing light. Slowly turn the dist until you get a spark signal. The engine should now start. Good luck.