I know everybody has a hard time with the 4 Phillips screws when taking the Phantom shell apart. I don't know if you really need to put them back or not .But to remove them after I strip them out.( At leased 2 every time). I use a 5/64 reverse drill bit. It works every time.Once had to use an extractor for that size bit.I get them at McMaster & Carr.Of course you will have to replace with New ones if you decide to put them back in.