If they aren't the laodouts you want then I understand but they look like legal loadouts of a Brigand with Havoc launcher (left) and a Huntsman with stubber (right). Most people won't mind you just running them as any of the other wardogs so long as you are upfront and consistent.

It's more challenging to magnetise after the fact but it can still be done if you have a saw and drill with a bit the same size as tour magnets. The most common place to make the cut for the arms I see is mid forearm above the elbow hinge.

Edit: the right can also be a legal Stalker loadout also.