Diggerdomer - are you using the correct version of the Catechism? There were translation errors in the version that was printed in the 1990s in the US.
The correct version and that printed on the USCCB site is: “Catechism of the Catholic Church, Second Edition, revised in accordance with the official Latin text promulgated by Pope John Paul II” and first printed in the US in March of 2000.
883 is very clear. It states that the college or body of bishops has no authority unless united with the Roman Pontiff, Peter’s successor as its head. And it clearly states that the power of the Bishops can not be excercised without the agreement of the Roman Pontiff. Footnotes at bottom of page state sources.
Regarding your second question:
“The Church respects and encourages the political freedom and responsibility of the citizen. (2245)
It is the part of the Church’s mission to pass moral judgments even in matters related to politics, whenever the fundamental rights of man or the salvation of souls requires it. The means, the only means, she may use are those which are in accord with the Gospel and the welfare of all men according to the diversity of times and circumstances. (2246)”
This means the welfare of ALL men, including the Church’s teachings on “subsidiarity” 1883, 1885, 1894, 2209.
Everyone, please check the copyright page in your Catechism of the Catholic Church, Edition". Near the bottom it should say “First Printing, March 2000”.
If you don’t have a correct copy, you can use the USCCB web site. However, it is more difficult to keep everything in context just using a web site since topics are related.