There seems to be alot of mixed oppinions on the master cylinder subject for 94-95 stangs, some say you need the cobra m/s while others had no problems with keeping the stock one. But one thing is certain, you cannot use a 96-up m/s since those are setup with hydroboost (uses hydraulic pressure from the power steering pump). I'm getting ready to do the cobra breaks myself soon, and I'm still unsure what I'm going to do about the m/s, but I'm leaning more towards the '93 cobra m/s since the lines are on the correct side. At least that is what the consensus seems to be. Do a search, there are tons of write-ups on these, then you can be as confused as I am