I'm going to explain how I achieved the blue line measurement on my SR80i. Green line is with the comfy pads.
Disassemble your grado's using a hair dryer. Punch two holes in the driver (punch mod). Replace the grill or remove the button if possible. Perform the quarter mod (but with an internal diameter of 43mm) on the comfy pads. Cut two pieces of memory foam (from a pillow or matress topper), internal diameter 19mm, external diameter 43mm, depth 15mm.