Please note- Wiring the fixture to use LED fluorescent replacement tube is simply, but should be performed by a qualified/licensed professional observing normal safety procedures.
1) Disconnect the power supply to the fixture at the source. Do not simply switch off the fixture.
2) Remove existing fluorescent tubes and safely set aside.
3) Disconnect (cut) wires to ballast leaving enough wire to be tied off with wire nuts
4) Tie off remaining wires attached to ballast with wire nuts.
5) See wiring diagram shown below for fixture rewiring instructions.
6) Install LED Retrofit tube(s) into fixture.
7) Re-connect power supply and turn on switch.
Be aware that the two pins at each end of the tubs are internally connected together so you may apply line voltage to either one pin or both.
Never apply both HOT (usually black) and NEUTRAL (usually white) to the same end of the tube! The individual pins at each end are internally shortened.
NEVER attempt to retrofit or otherwise alter in any way, any fluorescent fixture with built-in emergency battery back-up. Doing so will immediately void the NFPA life safety code certifications.