Slingshot?

I think a slingshot can be made by creating a weaker bow&arrows, but I want link to be able to keep both the slingshot and the bow&arrows. Could someone tell me step-by-step how to do this, please? The slingshot should cause the same effect as it does on ZTP.

Well...

* Define four items: Slingshot (Bow), Slingshot (Arrow), Bow, Arrow. Give the "Slingshot (Arrow)" a Damage of 0 and a Duration of 25.
* On the subscreen, create four matching "Current Item" elements, all of which use Item Override.
* The "Arrow Ammunition (1)" item is a problem. Consider removing it or chainging it to another variety of Rupee or Clock.

Could you give me more details on how to set it up in the subscreen?