The adjustment stop bolt in the clutch slave cylinder bracket is there for a reason in the stock set up design. Use the stop bolt to achieve a minimal clearance between the throwout bearing and the clutch pressure plate release fingers. Once this is done, adjust the rod length so the slave cylinder is not quite bottomed out. This will give you a maximum clutch release situation (slave cylinder rod max travel) when the clutch pedal is depressed, but also allow for the release bearing not touching the pressure plate release fingers when the clutch pedal is fully released. You will have to use the original slave cylinder assembly release spring for everything to work in concert. If the clutch assembly is ever replaced after these adjustments are made with the old clutch, they will have to be redone upon installation of a new pressure plate and disc assembly.
If you change the design to an an internal hydraulic release mechanism, not sure how you can maintain the throwout bearing not touching the pressure plate fingers in the fully released position. Design of the spacer(s) when the hydraulic release mechanism and what type of clutch pressure plate and disc setup you are using? Sorta complicates things?