Regardingthefuel filter on my '03 Miata.
1) Do I need to depressurize the system before I disconnect it?
2) How to I remove the lines from the filter without damaging the clips?

 

Diagram below shows how to release the fuel line clips. Once line is off then transfer the little clip piece that stays on the filter back into the fuel line. You can depressurize the system by removing the fuel pump relay under the dash and allowing to run untill engine stalls but is really not necessary. Just hold a rag around the fuel line connection as you are disconnecting so it will not spray on you.