switch overlay

Hi Group,

I've built a remote control system(Rf) with a 16F873A. I have eight tact switches for different functions. I'm using Racon 8 switches with the small plungers. Link to the data sheet.
http://www.ittcannon.com/media/pdf/c...t_switches.pdf

It's all good except I'm a bit confused on the switch overlay. The data sheet shows that the overlay should be slightly raised, is this necessary and something you specify when the overlay is made?

Suggestions for companies that make overlays would be great. I only need a few inlays.

Thanks,
Steve