I usually take out the number one plug (front plug, left side), stick my finger in the hole and tap the ignition until the cylinder pops (or you can use a compression gauge). Then I make sure the timing mark is aligned at TDC. Next I remove the distributor cap and check where the rotor is pointing. According to previous posts, it should be pointing at a spot between the firewall and master cylinder, almost under the wiper motor. This may take several tries at removing and replacing the distributor to aim it there, as the rotor turns when you engage the camshaft gear, be sure to engage the oil pump shaft and the distributor seats all the way down. The vacuum advance on the distributor should also be on the left side. This will place the adjustment window aiming towards the rear of the right valve cover, and accessible for your allen wrench after you get the wires installed. Next make sure the number one wire on the distributor cap sits over the rotor in the proper position. Pontiac firing rotation is counter clockwise, 1 8 4 3 6 5 7 2.