Steve - You have to plug the vacuum line to the distributor to check the timing. And if the distributor is not set properly, it has to be pulled out of the engine to be corrected. To check this you need to find where number 1 is at the end of the compression stroke by using your finger over the plug hole. Then turn the engine to align the timing mark, it shouldn't take much. At this point the rotor should be pointing at the #1 plug hole. This is where #1 plug wire should be connected to the distributor cap, too.
Also, these engines can usually be turned by hand. With the wheels chocked and the tranny in neutral, you can usually turn the engine with the fan blade, even with the spark plugs in, if the belt is set a little tight.
Personally, if the engine is running good, I would leave the distributor alone. And don't pitch the timing light, one day you might need it when you upgrade your engine.
