Whether you are replacing your distributor or fitting one because your ride needs it, here's how to go about getting the job done.
First off, remove the right side valve cover from the engine. This side is where cylinders 1 and 2 live.
Front right is #1 cylinder. Moving clockwise, turn the engine until you see the exhaust valve open, then turn some more until you see the intake do the same and close itself. This is the compression stroke.
Turn the engine until the pulley notch points straight up or the woodruff key is facing 9 o'clock. This is TDC for cylinder 1, and we can now continue to the next step.
After removing the distributor and its clamp, slide the clamp and o-ring onto your new distributor, making sure to fit the clamp first of the two.
Check how the drive notch is lined up (look in the distributor hole), then apply oil to the o-ring and distributor shaft and put it in. If it doesn't all go on straight away, give the rim a gentle tap. Slide it down until it stops on the clamp. If this doesn't work, rock the rotor on the drive gear back and forth while sliding the distributor gently downwards. It will drop the rest of the way once you find the notch.
You want the rotor to be pointer at the distibutor's notch. If it isn't then either #1 cylinder is not at TDC, or the drive pinion is not indexed correctly. This means removing it and rotating it to the correct position.
If you're reusing a distibutor cap, you'll need to make sure the rotor is pointing to #1's plug wire. If not, remove the wires and move them into position.
Now time the engine. 009s can be set to 30 degrees btdc at 3.5k rpm or higher, or 5 degrees btdc when idle. Both settings are equal.