Okay, here is what I discovered.
The first couple pics of the installed throttle cable show a piece of metal going thru the slot of the plastic housing inside the firewall. Can't say it's original or not but looks to have been in place for a while.
The next few pics show a shim for front end alignment. It may actually work as it sits in the recessed area of the housing although I didn't try it. But looking at it seems to be a pretty good way to secure the plastic piece. A very thin shim would do the trick in my mind.