If you do go the distributer route, you don't have to pull the distributor all the way out to do it.
First determine which way you you have to move the rotor; if you can't move the distributor any further counter-clockwise to reach you timing mark them you will have to move your rotor clockwise a tooth, and vice-versa.
Second, loosen the hold-down clamp enough so that it can be moved back far enough to allow the distributor to come up out of the hole.
If you have to move the rotor clockwise, it is a piece of cake...just slowly twist the rotor clockwise , and the distributor will lift out of the hole as the shaft rides up the cam gear and releases itself from the oil pump. As you are slowly twisting it, you will feel it drop down as it starts to mesh with the next tooth on the distributor. Start rotating the rotor counter-clockwise until it will go no further. The shaft will not be aligned with the oil pump, so the distributor body will not drop completely down into the hole. To get it to line up, bump the starter once or twice. Loosely install the clamp and time it.
If you have to move the rotor counter-clockwise , it's just a little bit trickier, because you have to twist it clockwise until the distributer just releases from the cam gear, then lift the rotor/distributer just a hair so you can then rotate the rotor past the tooth you were at and grab the next tooth going counter clockwise. Re-aligning the oil pump is also done by bumping the starter.
You should probably disable the ignition prior to bumping the starter. If it's HEI, just unplug it. Points: disconnect power to the coil.