John,
As you probably have seen, Steve Thomton went with fuel injection on his Rally replica BJ7. Since he went to a lot of effort to make it look like a period car, I thought he may have figured another way to convert to electronic tach. Looking at the video, though, he has replaced his tach with a black faced one (see near the end of the vid):
Some of the Sprite guys have been using Speedhut gauges, who will custom make just about any dial face and even use your own artwork. This one may work for you if they did a new face: https://www.speedhut.com/gauge/GL4-TACH-02/16/Tachometer-Gauge-8K-RPM Here's a link to one of the Sprite discussions: https://www.britishcarforum.com/bcf/showthread.php?94580-Speedhut-Gauges&highlight=speedhut
I have some custom Speedhut gauges they made for a 308 Ferrari I'm rebuilding. Good people to deal with. Here is the set I had made.
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John
Nice cavallino rampante! Don't know if it matters to you, but if you try the Stewart Warner gauge transplant, the gauge does not park at "0" when the current to the gauge is cut off. It will keep a reading between 2-3k on the needle. Once you power the gauge, it will zero and provide proper RPMs when the engine starts.
Hi John,
Do you have the injector kit yet? It may tell you (or AH Spares could) what kind of signal the ECU puts out. When I installed a Jacobs ignition, my BJ8 electric tach wouldn't read the signal. I had to have the tach converted to read a square wave. North Hollywood Speedo did the work for me.