From what I can recall from the talent text it specifies "weapon effect" ... to me, a character using two weapons is an effect originating in the character's action, not the weapons themselves. Auto-fire is a weapon quality, or weapon effect, that is inherently part of the weapon, like stun, defensive, deflection, disorient and other active qualities. Two weapon fighting is not, as I see it, inherently part of the weapon's qualities, nor a weapon based effect, but it's skill based.
Now, I'm not saying that jury rigged should not be allowed to do this, but strictly speaking I do not see it as allowed as things stands. If I'd allow I'm not sure, although I'd probably require both weapons to be jury rigged, as a sort of "pairing quality" of the two guns. Alternately an attachment could be made, "synchronised targeting" or something, which at its base makes the two weapon into "one" weapon with a linked 1 quality - which then could be jury rigged... that's the long and roundabout way though.