Ok, found out this mod is even cooler than I thought ... but i'd like to suggest a few tiny additions.
1. a separate nixie tube dot (a lamp with the color of the tubes) it should have the same logic as the tubes have, means if placed like this (T=big nixie tube, D=dot) TTTDTTT it should show all numbers up to 999,999 even though the dot has only half the size of the tube. Also dot only lights up if value is bigger than 999

1. in case of small tubes or if the dot isn't used ... a dot should show up on the tubes itself (in the one with thousand or above.. and the one with a million or above)