Flip the tonearm over so you can remove the two small screws that hold the bayonet in place.
Use a firm grip and take your time. Once removed you need to use some carefully moderated force to pull the bayonet out. I had to resort to a little sideways back and forth force to loosen.
Then cut those wires close to the bayonet. Leave enough length so the main wires won't go back inside the tonearm. Don't worry about the orientation. You can't put it back in wrong.SPECIAL NOTE:
You want to solder wires to the headshell BEFORE running through the tonearm so you know how much you have to "play" with.
Put an empty headshell back on the bayonet to act as a heat sink.
Pull the insulators off the cartridge pins and slip down on the new wires, away from where you'll solder. You want to reuse these. Or if they are in bad shape, get some 3/16" heat shrink so you can protect the solder points from each other. I have a pair of needle nose pliers that are round points and smooth, so I was able to pull from the end of the insulators without tearing them.
Solder one wire at a time. I was able to melt the end of the new wire about 1/8". Then heat up the solder on the tag, holding the wire close enough to slip into the molten solder. I had to do a little touchup to get the solder on each wire clean and smooth. Some of this was finished after I took photos.
Insulation back on.
Now you need to solder the end of the new wires to the old. Actually, you should try one to one wire. I tried the whole bunch and the connection broke twice. I figured that if I soldered to ONE wire and it didn't work, I'd have three more . . . more on that later.
It's "later" already, so here's what happened. After unsuccessfully trying twice, I just pulled the four main wires out. In this case, I left the stock ground wires in place. I took a piece of the stock external ground wire and soldered the new Cardas wire to it. Then I put some heat shrink on it.
I love this cool heat gun I bought at Fry's Electronics for $15. It has a nifty metal stand and switch. (I want to heat shrink more stuff, anything!!)