So, now that I've taken up everyone's time with my tweak nonsense...
I thought I'd try to be helpful and mention that for anyone who used to use a straight bar, or the use of a friend to hold the chassis flat, while detweaking, a standard paint stirring stick works very well on this car. The "handle" of the stick has cutouts, as seen
here, and when appropriately positioned straddles the spur gear, sitting on the flat spot of each diff/spool cover. Also, they happen to be free at most paint stores.
Yea, that's the best I have today.