On the Strings reversed on the E and A, put the bass side gears lower than the g/d gears if it will get an Extension to play safe. If not, the reverse is ok with the G the lowest to extend the E. Overall, the regular way with the E on the A post is my favorite and most versatile. If putting an Extension on with the Gears reversed (G the lowest) then if an Extension is installed, the upper gear may be too far and the string can cut into the peg box or the lower Gear might be too low.
This also depends on the length of the gear box itself as well as the pitch or curve of the pegbox and the way the gears are installed.
Over the next few weeks I have a few Shows to do locally (South Pacific) and an Orchestra concert as well doing some Ellington and Gershwin. I will use my Mougenot for both jobs, currently strung with Evah weichs and put the E on the upper post as well. This bass was made originally as a 4-string which is typical for all of the Vuillaume Basses. The
Mougenot has an extra long scroll/pegbox as well pushing everything up at least another inch (web pics show old string tuning). With those big ear handled French gears, the longer 'box is a blessing for my knuckles when changing strings or even just tuning the bass.