go the Pajero master cylinder, they are easy to find and are already designed for large calipers, i have one and will be running Hilux 4 pot calipers and JDM T series calipers, steroid chickens also has this set up.

but you will need to get another piece from a ford laser linx to make it all work.
should look like this when its complete.

this is the MC on its own.

this is the bit from the ford.