No need to apologize

. About that...
The Soviet 82mm mortar is a 82mm mortar

. The 107mm mortar is a completely different one and their heights are definitely not equal.
Also I just looked at the at guns and you are half wrong in that. ZiS-3 size is fine as it shouldn't be larger/equal than a pak 38, but ZiS-2 is a bit smaller. However, we are not going to discard this model and make a new one with the right length because we have a lot of things left to do and this one is really a minor one

. Or at least that's my take on it.