Replace the clock with an AFR gauge....much more info about your cars running....I have a cigar lighter volt gauge...

I purchased a VDO Voltmeter and used an old clock housing (which it fit into nicely) so it looks like a porsche instrument. Total cost was around 100. The other option is to contact jbell on this forum and he can do wonders with existing gauges, ie send in your speedo or tach and he will add a voltmeter.

For pennies you can buy LEDs which flash three different colors. They can fit in a small grommet in a hole you drill in your dash. I rigged up one, and I connect it across the fan/alternator warning light. If the fan belt fails, it flashes. I included a variable resistor tucked behind the instruments, as these can flash bright enough to be distracting at night. You are reducing the voltage anyway for the LED unit, so this lets you make it work without having to calculate resistor values.

The NH VDO clock dash pictures look like it is set up for four such indicator lights (or are those just dash upholstery attachments?).

With only a minimal knowledge of electronics a guy ought to be able to make a gadget which would close a connection (or open one) when the battery voltage rose above some level, or fell below some other level, causing one or more LEDs to come on, etc. Flashing really catches the eye, much more so that a somewhat dim red light in an instrument - especially in daylight.

I used a VDO 332 304 007 001 dated 9/72. It’s a push-in gauge
The hole size is about 2-1/4” and the bezel is about 2-1/2” It looks nice being bigger than a 2-1/16 gauge
Not sure where I found it.http://forums.pelicanparts.com/uploa...1636196444.jpg

Good tip, thanks for sharing. They seem to be readily available and aren’t expensive. https://www.google.co.uk/search?q=VDO+332+304+007+001&ie=UTF-8&oe=UTF-8&hl=en-gb&client=safari