No its a late 71. These holes are for screws and way too small for alignment holes. The look like they were used for something in the past. I'll try to get a pic today. I have a original 70 strip that was on the 70 but not the 71/72 Wonder why they deleted that for 71/72? Anyhow the fact that the holes are there is strange to me. Unless the rear pan was common to all A bodies.
John, The small hole in the cross brace above the filler tube is for a black plastic strap that holds the gas gauge wire. I have only seen the rubber strip on 70 cars. The 70 GSX I'm doing now has it.
I think I have this figured out look at the car I just picked up. With the bumper removed you can see factory undercoat sprayed over one hole on the pass side nit the drivers side is open. Never had a screw in these holes. On Olds and maybe all A bodies share this panel the center may be used for a strap like Steve said but on an Olds it has a strap to the filler neck. I just saw a couple. The Olds also has flaps on the outside where the first set of 2 holes are and Maybe others too. Not on a Buick however
