if you use action replay DS, you might notice that in your mail slot, there are 95x explorer kits that you can't toss, so you can't get rid of them.
but if you use the x999 colour mail(or any other type of mail) cheat, your x95 explorer kits will be replaced with x999 colour mail(mail depends on the type of mail cheat you used), which you could toss, so simply toss as much as you want, and save the game, and your x95 explorer kit problem will be solved.

and by the way, if you use walk through walls cheat, make sure you don't save the game while the cheat is in use, coz if you go through walls, cause a glitch and save it, that glitch will stay there.