every vehicle I have disabled the dinger from, I just yanked the circlular relay thing from under the dash.
let it keep dinging (leave your keys in, but in off position with the doors open) and mess around under teh dash until you find the one thats clicking with the dings. you should even be able to feel it click if you find the right one. yank that.
you might also want to check your manual, see if theres a way to turn it off