I did the same thing....I forget exactly which wire to cut, and my car is in New Mexico while I'm in North Carolina, can't exactly go look at it. Hope this gets you in the right direction though....
I pulled the switch out of the drivers side door, it looks like a little button, it's on the forward side interior, same location as the hinges. There are 3 wires, two power, one ground. one is for the chime, the other is for the interior lights, and the other is like I said the ground. Here is where you can get out a meter or test light to figure out which is which, like i said I forgot.
Dirty way to do it would be to cut one wire at a time, see what stops working...maybe you get it right the first time, if not just splice it back together.
I believe the gray wire was the ground, so you can leave that alone.
Not the best info, but as I said hope it points you in the right direction
good luck, that chime was horrible, glad its gone.