Sorry, I should clarify - I'm aware I need to use a child config but I'm not sure what variable I need to change in order to hide the ATGMs.
For the gunnerType parameter - in the GREF configs I found gunnerType in rhsgref_cdf_t72ba_tv/Turrets/MainTurret/Turrets/ under CommanderMG and CommanderOptics, however under MainTurrets itself it appears to be empty. I'm unsure what to do because in my case I'm specifically trying to change the gunner unit in a BMP. Would I need to change the gunnerType variable of [BMP]/Turrets/MainTurret?
(edit)
I tried doing so and it seems that it just breaks the turret configuration because the other variables from the MainTurret class aren't preserved when I make a redefine it with the gunnerType I want.