I can't tell the avocado type from the seed. (Maybe Reed, if the avocado was also roundish without a narrower neck?) Do you have a photo of the avocado itself? Or can you describe the shape, color, and texture of the peel? Can you ask about the variety at the place where you bought the avocado? The produce manager may know, or be able to find out.
Years ago, I used to try to grow every avocado seed after I ate the avocado. The only method I used was to suspend it in water using toothpicks (similar to cocktail sticks?). I had a very high success rate, but I didn't live in a climate where an avocado tree could survive outdoors. At one time, I moved away and left my housemates with a dozen or so avocado seedlings!
I don't think the nails will damage the pit, since it is so large. You could use this variable as another part of your experiment. You will have to eat many more avocadoes to test more variables! I wonder if a bulb-forcing vase might also work, if you have one of those on hand.
As for technique, just make sure the correct side of the seed is facing up (the pointier, less flat side), the soil container has sufficient drainage, and the water in the suspended container is changed regularly.