A body K member

Nothing wrong, especially safety wise with a 67 Idler mount. I call BS here. I have a 67 Barracuda with 400,000 miles on it no problem with the Idler mount. Worry about something else. The only K Frame I have seen messed up is a 73 up due to sloppy or non-existant welds. It was replaced with a 67 K frame and is probably still fine.