Any source for a tremolo spring cover routing template?

[pipelineaudio]

I'm going to try the Fishman Strat battery, which replaces the tremolo spring cover on a standard fender tremolo spring cavity. Due to its depth, I'd like to route it in pretty far. My tremolo block has plenty of clearance. This template would pretty much have a hole the size of a standard cavity cover. Plexiglass would be ideal

 

[Eagle]

Make one.