The arm that rides on the cam lobe has a downward facing hook. The diaphragm has an arm with a loop on the end. You drive the pivot pin for arm out then it should come apart. Start at the 4 minute mark in the video below. FWIW you can often get it to come apart without driving the pin out by pushing down on the diaphragm while leveraging the loop on the end of the diaphragm shaft away from the hook on the cam lever arm.

https://www.youtube.com/watch?v=2tKXYCi4sQg&t=233s

You don’t need to remove the pivot pin, push down on the center of the diaphragm while tipping it away from the arm.you may need to hold the arm while doing that. I just had the one off my 54 apart with no problem.

Thanks Tiny and Dennis. I will get a little heavier hammer to get the pin out as I did try several times pushing down on the diaphragm with no luck. I think I watched a dozen Youtube videos and none mentioned removing the pin. I will post my results.

Got the pin out and removed the diaphragm. Noticed the diaphragm did not line up square at the link as the mounting holes are off by about 1/4". Also there is no seal at the diaphragm push rod as mentioned in my repair manual. Is one necessary or something that some have decided it is of little value. Other than if the diaphragm fails gas will go into the crankcase. The diaphragm is new .

I am no expert but I've never seen a seal on the push rod unless it's referring to the gasket between the flange and block. A leaky diaphragm will often result in some fuel in the crank case. You should see dripping out of the weep hole if it's compromised.

@tiny I bead blasted the housing and assembled the bottom part. Tomorrow it will get assembled and installed. Thanks for the help.

I'm happy you got it figured out. As you discovered, getting the diaphragm loop to unhook from the cam lever can be a challenge. I don't like having to drive the pin out but sometimes it's just easier that way.