Jay,
I mounted my home made bracket on the rear capscrew on the motor side (top) of the motor mount. This keeps the slave cylinder moving with the motor, not attached to the frame. It also allows the cyl. to "float" between the heim joint at the front and the clutch arm in the rear. This eliminates any binding of the piston / rod in the cylinder. I agree, the heat problem is a serious issue, so I made a "better" heat shield.