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The current circuit I was thinking of building is something like this:

I currently have a ~6.5W incandescent lamp in parallel as a power indicator. However, the client (my wife) wants an illuminated switch (lit when switch is closed) instead of a separate lamp.

So, I found a 12VDC 30A illuminated SPST rocker switch, marked "R13-133", with three spade terminals, marked Ground, Load, and Power.

I am having a terminal brain fart. After removing SW1, do I just connect +12V to Power, node A to Load, and GND to Ground? Or am I missing something?

It is tempting to think that the Load is the high side of the lamp and one terminal of the switch, Ground is the low side of the lamp and Power is the other side of the switch so that the lamp comes on when the switch is closed.

Have you tried buzzing out the terminals on the switch to see how the three terminals are connected and to what?

(Sorry, I can't post a circuit right now CL's editor seems broken at least on my machine).

Yes, when the switch is closed, Ground / Load read about 25Ω (lamp), while Load / Power are near zero. Ground / Load resistance drops to 0 when the switch is open, which to me makes sense. If I'm reading you right, I think that's what you described, and what I initially thought in my first post. Sound right?

Here's what I think the switch looks like, and how it would connect. Does this look right?

Thanks for the very basic help on this. Twenty years away from circuits (and I was no wizard then either) is really testing my memory.

Yup, that looks right.

Hmmm, a lot has changed in 20 years but the basics are the same ... just smaller!

:)