hey
i was reading the problem you had with your master cylinder i had the same problem aswell

change it but i didnt use oem master cylinder it was ohk for 2 weeks then after the pedal felt like there was to much freeplay not enought clutch pedal.

so to fixs the problem look at the master cylinder and there should be a 12mm nut loosen that and you can spin the nut with your hands make sure you spin the nut all the way to the end of the tread then get a pair or plyers and start turning the shaft or rod anticlockwise its easier to mark the rod with a black line so u know how much full turn u have done at first when you start to do it just do 3 full rotation turns on the rod and u should feel the pedal gettting firmer and then try it with your foot to test it if not firm enought keep adjustinng untill it gets firm but not to much tho. try not to loosen the rod cause is can cause the rod the pop of the thread housing and its a pain to put it back on. try that see if that helps