Swapping out weapon systems on vehicles

[diabolical 428]

Hi all

Im currently playing around with some of the arma 2 models and porting them over to A3. I've got most of what is needed sorted out but I want to experiment with having different weapon systems for the base cars.

for example what would be the best way for me to replace an M2 machine gun with lets say the DSHKM on a landrover.

If any more info is needed just ask, thanks in advance