Arduino nixie v41 Operating Instructions Manual page 21

Hint: Trimming the extra pins on the RTC module
ONLY if you want to mount the RTC
module directly onto the main board (you
can also do it via flying leads), trim off the
pins "32K" and "SQW" using a pair of
precision side cutters.
If you want to mount using flying leads,
you can skip this step and use the four
holes on the other side of the board.
Hint: 2N7000 mounting
To mount the 2N7000 FET, bend the
middle lead back slightly. It will then fit in
the PCB without problems.
After you have wired everything up, it should look like this:
Note that here I have put the RTC module directly onto the main board. The battery goes in the RTC
module with the back (with the writing on it) upwards.
RTC Module with pins removed
2N7000