great so was mine. Apparently a few common places were wrapped around the wiring harness under the dash,under or in one of the seats.... but for the Metuchen cars I read th efavourite place was in the rear foot space behind the passenger side door under the rear carpet.
So i looked there when changing my carpet and found...
build sheetsadly , i was an amateur when I uncovered it and used the wrong solvent to try and remove it and wrecked the damn thing. If you go looking, make sure you have a good degreasing solvent as the tar in the underfelt will have melted to the floor. If you find it and get it off- you should be able to soak it in the solvent if needed.