Thanks, Kurt, for providing that link. I chased my way completely through it (and another linked imbedded therein) and came to the conclusion my late 05E car, with its VIN that calculates out to be an "off the line" date of Monday, June 2nd, may or may not have had this clip installed at Norwood. So this is an easy decision for me -- I can look for a $500+ original clip, or do nothing and be correct.
Having said that, and being a retired chassis development engineer for one of what we use to call "The Big 3", I went right out and bought the $22 repro bracket the moment I discovered it in the '69 AIM. In my experience, the right type of vibration (frequency and amplitude), for a sufficient amount of time, can loosen any joint, no matter how expertly tightened or how perfect (or imperfect) the mating parts are made. Given the significant mass of the brass Y-block hanging several inches off the carb, I can see why the Chevy chassis engineers developed and released this support bracket for production -- to "calm" things down at the joint between the fuel tube nuts and their terminus at the carb and Y-block. It would never have been released if they didn't eventually see actual evidence of its need. This bracket can legitimately be called a "critical safety" part, in the same manner as the innocent looking clip that retains the brake booster clevis pin in the brake pedal. This brake clip should rightly be considered the single most important part on the car. If it were not there, or if it failed, one's very life comes into jeopardy. An undiscovered, top of engine fuel leak, no matter how small, is in the same category and is to be intelligently avoided, and easily can be, for a mere $22. In my humble opinion, every owner of a '67-'69 Camaro with an engine that utilizes the brass Y-block would do well do install this support bracket. Sorry for preaching, please forgive my impertinence.