I've studied the picture in my 69 AIM. Remember we're talking about a Holley here, not a Quadrajet as it looks like in the AIM. The inner hole has to fit over the carburettor mount stud (L78 & L89) As I said, for that to happen the corner of the bracket and outer hole has to go between the base and metering block / fuel bowl of the Holley. The bracket is too thick to slide in there. I've seen photos where some people have cut the outer hole of the bracket off to make it fit. I'm sure they didn't do this back when GM fitted them.