how does it ground ??

View attachment 1716234300

On my '67 its a wire with two ring terminals the other end going to the radio supportscew where it mounts to the dash.
View attachment 1716234303

IVR on the Rally panel grounds as shown here
[URL]https://www.forabodiesonly.com/mopar/threads/gauge-cluster-issues-ivr.455893/post-1972855400[/URL]

Mattax, I think the IVR circuitry is located in the fuel gauge in a rallye dash. The lead you are showing is a ground for the noise suppresser.