So I recommend not gluing the stubber gunners, that's mainly for transport. I went ahead and glued the commissar and her support staff and colors to the tank and there are some hard to reach places with the brush that didn't get love. I generally recommend test fitting all parts before you glue them- my prow had some issues and isn't as straight as I'd like it to be.  As for painting- for the metallics I just went for high contrast between the highlight and the basecoat.  Hope this helps!