I thought S-Car-Go racing in Marin has a high HP clutch solution for the monster motors they make. But a quick check of their website does not list. You might want to call Rob King.
You can also search for user "Poorb0yw" - he installed a
Tilton clutch, don't know if he did anything to the hydraulics, but when you see his car, it will be hard to believe he didn't touch it.