Bong, bong, bong???
I have a '98 convertible. I had (and still sometimes) have that bonging door ajar sound when the door was shut. It sounds like that switch in your door that does the dome light and seatbelt is weak. I wish you didn't cut anything. What I do is fold over a few napkins from the drive thru window and tuck them over the switch, then shut the door. Fixes my problem. They stay put quite well and when I need to re-wad the napkins, I do it. If you can put the wires back together and try my idea, it may work. I'm thinking this is what your problem is. I had this problem too.