This idea of a cheap switch came from another source (somewhere on the Internet).
I use those metal clothing snaps (bought in Fabric section at Walmart) as the "switch" for my on board glow setup. They are cheap, light, and easy to setup. Plus it provides an easy "visual" method to see if the system is on (snap together) or not (snap apart). Just cut the negative wire, crimp male end of snap on one side, female end on other side, done with switch.
This setup is great for all setup of engine (inverted, sideways, or normal). Especially for four-stroke that runs on low nitro fuel.
Fly NB