Thank you for the info.
Stock caliper was toast. went with the gold spot R1. pistons are 26.8mm and 30mm. Smaller than the stock at 33.8mm.
This gives area of 2542mm^2.
Looks like a 11mm master will be best for a ratio of 26.75x from the area of 95.03mm^2.
Will find a dirt bike unit to use. The external brake switch is the biggest tun off but how it goes.