Sc/Rambler specific Minutia needed(tach firewall grommet)

Q:One of the firewall sealer plates seems to be unique to the sc/rambler. This is where the tach wire comes out of the firewall in the engine compartment (drivers side). Do you have a v8 Rogue to check? Looks like that plate had two or three different configurations and the hole was used for different things. Sure seems to be a strange place to run one small wire and a bug rubber seal? Need to know. Thanks, Mike

Here is the part :