Add armor to the body without long weight paint After character export from Unreal Engine, I have one merged mesh with vertex groups (terrible export, had to add 110 to Z coord of every static mesh). The body has the weights I need, but armor doesn't.
 

Do I really have to paint all these 100500 vertex groups manually? If I don't use "limit selection to visible", I will paint something I wouldn't like to. 

If I do, I won't paint the inner part of the armor and there will be ugly tentacles. And if the body has "green" weight, I won't be able to paint armor correctly. 

It would be great if it understood what's armor and assigned correct weights to it. Or at least can't I select the area and assign weight to it? 

Blend file: https://files.fm/u/zaefgsjz
Enter edit mode, select one vertex of the armor, shift select a vertex of the other piece of the armor, Ctrl L to select all linked vertices, in the vertex group tab click assign with a weight of 1.0.





Another workflow: select a vertex from the body, Ctrl L to select all linked, H to hide the body, switch to weight paint mode and do all the paints you need (Face selection mode must be on, with all the vertices selected), Alt H to make the body reappear.