I'm not sure, whatever the king flutter shim that Filthy sells is. and its .008, not .08.
The double flutter setup I recommended comes from the DSMS taco OEM replacement King, I'm not that clever. I did have good luck playing with the progressive stack you discuss and a flutter shim in the 2 or 3 spot in the stack.
I'm currently using a 2x14 smooth body king, with 20, flutter, 18,18, 20 20, which I really liked for the washboard and potholes we get around here. When I get the front dialed in I'll have to re-visit though.