It's an optional hole in case you want to avoid blocking the fuel filler door. I don't think it matters for those of us with Fastguns. BTW, Torklift has manuals on their site as well as youtube videos.
http://www.torklift.com/documents/products/tiedowns/faq_tiedowns.phpQuestion: The chain/turnbuckle that connects from my anchor point to my tie-down is passing right across my fuel door and now I can't open it. Is there anything that I can do to correct this?
Answer: There are two ways that you can try to help clear your fuel door. The first option is to use the FastGun Lever Action, Springloaded Turnbuckle. When using the FastGun, simply lift the lever to disconnect the fast gun that is blocking your fuel door, fuel up your truck and reconnect the fast gun to your tie down and camper anchor point. The second option is the welded on triangular bullet plate, you will notice that there are two holes on the triangular plate - one at the pointed end of the plate and one above the insert arm on the tiedown. Simply move your chain/turnbuckle from the hole at the pointed end of the triangular plate to the hole located above the insert arm.