I couldn't find a "lip" between the housing and the bowl of the carb (where the diaphragm edge sits) that I could get a bite on with any tool I had.
I looked for a tool that I could pull up on the brass shaft that moves the diaphragm. I ended up using a wire stripping/crimping tool because the "teeth" are rounded with no sharp edges. I grabbed the shaft and placed a thin sheet of scrap rubber on the top of the carb bowl to use as a fulcrum. I pried on the handle of the crimpers which pulled straight up on the shaft and the diaphragm assembly finally let go of the carb.
Like Dan's, some of the flange part of the diaphragm seems to have turned to glue on both sides.
Enough for today.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| 
