Another method I was going to try was an edge squonk hole...I've been playing with making my own covers, I think on one of my Grands I'll make a cover with no hole, stick a Vmod 10ml bottle in and mill a narrower, more elongated "middle/ring finger" hole on the edge...I've got a similar set-up on a dual 18650/Vmod 10ml bottle mech mod in a Hammond 1550P box I'm just putting the final touches on...mind you I didn't have much of a choice with that build as 2 batts and a bottle is wider than the inner dimensions of the box (by 2mm) so I had to mill a side slot so the bottle's edge is exposed...super easy to squonk and looks kinda cool.