Set default attach point when right-click and "ADD"

[Bronsin Dakota]

Hello all.  This is probably very basic but I want , when a user right clicks my hud in their inventory and selects "ADD",  to attach the hud to a specific screen location like lower left.
I can find docco on ATTACH_POINT, the attach event and scripts about attaching when you rez and object and touch it. 
But not on setting the default when you ADD ?   I want to make this as easy for the user as possible.
Any help is greatly appreciated !

[Jenna Huntsman]

You can't do this with LSL.

That being said, the 'default' attachment point is the last used attachment point, so if you distribute a HUD that you've already equipped on the desired attachment point, the users will equip to that point by default.