That might be a stretch. OmniMech technology was developed by the Clans specifically for that purpose, and while the Inner Sphere has OmniMechs of its own, they're not common. Altering a Mech's equipment is not a quick, simple, or cheap task - rerouting power lines, moving armor, adjusting internal structure, setting up ammo feeds or capacitors (hence the whole argument that just went on). The advantage of an Omnimech is that is can routinely swap out its weapons with pre-packaged 'pods' between fights, and the Wraith is not an Omnimech design. You'll probably have to decide which of the two weapons you like more and stick with it.