That depends on how many AT guns the US player has deployed in a sector.
We are playing this currently and (I am figuring you mean the 3¡± AT Guns although there are the 57mm guns as well) at this point
the US player has not deployed more than one 3¡± gun in any engagement - but could.
So, you need 4 total but probably, at least at first, will not use more than 2.
Hope that helps.
BTW, if you are the umpire (like me) you will know what the deployment is before the German player(s) pick their attacking sector so you should not be caught off-guard
Best,
Mitch
