72 Demon Trunk lock cylinder falls through panel hole???

Yes, I did find a cylinder in my scrap stuff with the nut on the back.. It fit right in the hole and fits fine??? Why this 72 Car is now sporting the larger lock cylinder with the nut on the back is anybody's guess. I am thinking somebody ordered a cylinder back in time and mistakenly got the larger one, so rather than return it, they filed the hole open to receive the larger cylinder. So I will order a 73 and up cylinder and I think the problem is solved. Paintjob is saved. Thank God...