I will try and get this right, its not my idea but have seen it here many times.
First step is to set the #1 piston at top dead center on the compression stroke. Pull the plug and turn engine over till you get compression and the timing marks on the balancer line up with 6* on the pointer.
Step two, set distributor so rotor is lined up with #1 plug terminal on the cap. Check firing order on all other plugs at same time. It doesn't matter which direction its pointing as long as the wires are in the correct order and the rotor is on #1.
Step three, with plug still out of #1 cylinder, ground the plug case to the engine.
Step four, turn on the key to run (DON'T TURN OVER ENGINE).
Step five, turn distributor housing till the plug from #1 fires. Go past this point and come back till it fires again. Now split the difference and lock down the housing.
Step six, turn off key, reinstall plug, and fire up engine.
Step seven, pull vacumn advance and set timing to factory spec's.
Hope this helps, Joe