I don't know how to do this, but i know it can be done..... You can set up tag as a toggle.. so it is always on in it's own group. Must use some sorta macro.. I'm sure if you asked how to do it, or search it, the info is around.. or someone would be willing to help.. I just don't know the answer outside of it is possible. That said, Always on tag is one of the easiest ways to find a mech.. the thing should be infer-red, so only you can see it, but that is a whole other topic
But as to your main Q, i always just group my weapons separate, and hit the keys when needed... Not to hard to click 2 mouse buttons at once, as typically that's all i have.. on the rare occasion i have 3 groups, the split second isn't a big deal.. especially as they are typically on torso or arms.. and with arm lock off, moving the mouse to keep hitting the same spot, with a tiny pause is always better than a pure alpha when things are not lined up.
Edited by JC Daxion, 25 December 2015 - 05:32 PM.