The metal retainer in the grommet that seals the emergency brake cable to the firewall in my 68 Dart is rusted through and won't hold the grommet in place anymore.

Is there a source for these anywhere? Is the only fix another cable assembly? Any help on this would be appreciated.

I bought a PB cable set from inlinetube.com, and the firewall grommet came installed on the front cable. It is solid rubber, without the metal piece inside, which the original had, as you mentioned. I believe the looks from the firewall side is virtually the same with either one.

Since Inline's web site does not show the grommet in their photos nor list it as a separate item, you'll have to call their tech support to get order info.

If there is a big clevice on the front end of your cable, you'll likely need to remove the cable from the car so you can wrestle the grommet on from the back end of the cable. Even then you might need plenty of KY jelly and boiling water to heat up the grommet.

OR, you can razor cut the grommet on a radius, slip it on the cable, super glue the mating pieces together, and pop it in the firewall.

Hints: When razor cutting rubber, keep the razor wet with dish soap. Any super glue that gets on the exterior will show, so keep the glue just on the mating surfaces.