Sun Super Tach

Yup. Go to the MSD site and read the destructions for your ignition. I bet you need a tach adapter

"Side note" Long before Al Gore invented the internet, I bought one of these when they FIRST came out in the early seventies. The "ads" in the hotrod mags "assured" us it would work with "electronic ignition." I did not understand, then, that CDI ignition was a "something different" These were the days of stuff like "Delta" and "Tiger SST." I fought that thing for a long time, and finally scored a hemi tach drive dist (dual point) which I promptly stuffed into the 440 with a huge Jones / Motrola tach

This was a big black face / white numbers. The 70RR came with a "tic toc" tach / clock which never worked. The original owner took it out and sent it in on warranty and never got it resolved. When I bought the car it had the old "two piece" Sun in there. The Jones very nearly matched the speedo in the 70 RR dash.