your questions have the correct answers. the other consideration is the hanger. A = richer Z = Leaner
i did a quick search on google.
https://www.carburetion.com/rodshang.asp
http://www.hioutput.com/tech/qjetrod.html
obviously before you make any changes, you need to find out what you already have installed.
usually around a G hanger and DA rod should be a good starting point if the Main circuit is setup correctly.