since it's all pretty much top loaded, all you should have to do is unscrew the jacks, pots, 5 way and switches, and it should all pull away. then you should be able to shielded it provided the pickup wires allow for the room to pull it all aside.
and unless you ground all that stuff, the pots, and switches etc..., your gonna want to shield it all. you WILL find a venue that will create rf interference and 60 cycle hum, that's inevitable. it's also most likely the crackle you hear already. you have to remember that while you have shielding on those input/output wires, the rest of that cavity is susceptible to that rf interference and 60 cycle hum as you have nothing to block it from getting to the 5 way, pots or switches or all the UNshielded wire in there.
"Tone is in the instruments. Technique in the hands. Do what you will." ~quote from some guy at the TGP forum
"Without a doubt, the quality of your instrument will effect your tone, and any pickups, effects, amps, and microphones used along the way will also have an impact on the sound waves."~Cameron Mizell