#2
I assume you mean pick guard as opposed to bridge cover since you're talking about the jack. I'm pretty sure you mean output jack too if you're talking about the place where you plug in the cord that connects to your amp.

If that assumption is correct, you need to remove everything that is holding the pick guard down - knobs, strings (most likely), the ring around the switch. After that it's a bunch of screws.

I might be forgetting something, but basically, take off everything that's in the way, and have fun putting it back together. Check your manual to set your guitar up properly. If you don't have the manual, download one from the Fender site.
#4
Haven't you heard that cutting all the string of a guitar at once can screw the sound?
Anyway you no longer need to reply since I already found out by myself :-)