Back then, the 50 (yes, 50) ARs were in the body of the book, but there was a separate book called the Official Football Rules Interpretations, which contained much text expanding on the purpose, intent, and application of the rules. That book also had dozens and dozens of "examples" to illustrate application of the rules and interpretations.
In 1976, the Interpretations book was directly incorporated (maybe 'attached' is a better word) into the Rule book (as we have today), and the ARs, that had been in the Rule Book, were moved into the Interpretations section. So, in the Interpretations section, there were both ARs and Examples. Not necessarily a problem, but the ARs held more weight than the Examples, if there was ambiguity or conflict.
In 1986, the Examples all became ARs, which is where we are, today (format-wise).
I don't think anyone would argue that having the applicable ARs located directly with the associated rules would be very, very convenient, and time saving.