A characteristic of the diaphragm type clutch is that as it approaches the end of its useful life it gets progressively stiffer--a condition often mistaken for a bad cable. 260 series cars had hydraulics for the clutch but they don't feel particularly light in that area. With a custom setup I guess you could engineer a lighter pedal, but a new clutch kit or at the least a disc would be a cheaper and more direct way to achieve a lighter feel.