John,
I was under the impression that the LF Code bar, etc, etc, had to be in the correct slot. In this stuntbox it is nowhere near the LF clutch.
Even though I have read how to remove the stuntbox, I don't feel confident enough to try it.
I have made the typing unit with the cracked casting my parts source. If I felt I could do it, I would swap the stuntbox from that to replace the one that does not line feed.
Have a nice Christmas. Talk to you when you get back.
Tom N3CRK