It won't go too far, but you can get in far enough to run, but not engage the oil pump. I just put my vacuum advance on as high as I could and once I got the distributor seated, pushed it down to the block, set it at zero, bolted it down. And adjusted the timing from there. If you want to see where the engagement point for the oil pump is, turn it to where you are certain it won't engage, then mark it there, then put it where it WILL engage and make sure you go past that point by what ever it takes to get it firmly seated. This is probably not the official way to do it, but it works. You don't actually use the octane selector to set the timing, as fuel now days is very standardized. I have never used it in 30 years. you loosen the screw on back side and move the distributor and time it using the ball in the flywheel which may not be perfect, but for the extra 2-3 horsepower I might get timing it some other way is just fine by me.
