If I understand what you want to do - you need to Change it in the individual aircrafts data.ini
eg
[LeftOuterWingStation]
SystemType=WEAPON_STATION
StationID=1
StationGroupID=1 <-------------------------------
StationType=EXTERNAL
AttachmentPosition=-3.47,0.37,-1.18
AttachmentAngles=0.0,-2.0,0.0
LoadLimit=1400
AllowedWeaponClass=BOMB,LGB,ARM,GP,IFP,MER,RP
AttachmentType=NATO,USN,UK
ModelNodeName=wing_pylon_outer_left01
PylonMass=52.62
PylonDragArea=0.02
[LeftInnerWingStation]
SystemType=WEAPON_STATION
StationID=3
StationGroupID=3 <-----------------------------
StationType=EXTERNAL
AttachmentPosition=-2.05,2.74,-1.28
AttachmentAngles=0.0,0.0,0.0
LoadLimit=1400
AllowedWeaponClass=BOMB,LGB,EOGB,NUC,EOGR,CGR,ARM,EP,TER,TLR,RP
AttachmentType=NATO,USN,UK
ModelNodeName=AdapterLeft
;PylonMass=
;PylonDragArea=
LaunchRailNodeName=
MinExtentPosition=
MaxExtentPosition=
[RightInnerWingStation]
SystemType=WEAPON_STATION
StationID=4
StationGroupID=3 <----------------------------------------
StationType=EXTERNAL
AttachmentPosition=2.05,2.74,-1.28
AttachmentAngles=0.0,0.0,0.0
LoadLimit=1400
AllowedWeaponClass=BOMB,LGB,EOGB,NUC,EOGR,CGR,ARM,EP,TER,TLR,RP
AttachmentType=NATO,USN,UK
ModelNodeName=AdapterRight
;PylonMass=
;PylonDragArea=
LaunchRailNodeName=
MinExtentPosition=
MaxExtentPosition=