Wilwood or aftermarket Master cylinder that works with kelsey Hayes Calipers?

Does anyone here run a Wilwood or another good master cylinder with Kelsey Hayes calipers? My 70 Swinger has the KH setup, but the stock style master cylinders seem to always leak and ruin the paint on my firewall. I looked into it, and the K H MC bore is 1 inch, the Wilwood I believe is 7/8 inch. Will this conversion work? Any other suggestions, my nice firewall paint is ruined and needs touched up. Not looking forward to it.