Husker recently recommended using blu tack to attach the button caps.
I tried it and it's really easy to attach and keeps the caps really tight in place.
Starting today all future kits will include a little piece of blu tack.
It's like sticky plasticine.
You just have to roll a sausage out of it

then cut it up in 39 little balls

and put them on the bottom of the caps

Waaaayyyy less fiddly than cutting up some tape!
Comments
I claim naming rights!
"huskerballs"
as in "Did you use huskerballs on your LXR? They are awesome!"
Apparanetly I searched around a little bit and the blu tack was the cheapest tack I could find on the quick :-/
either way cheap enough since you only need a small pice for the caps, so it costs me almost nothing to add