I can't belive it, I just built Vasquez and I'm a complete idiot when it comes to this stuff. Her harness is by far the most intricate, has cross straps, pads, attachments, smart gun attachments, wires. etc. As far as her head I would connect it after you have her body snapped together and have her outfitted.
Couple quick points, tuck her shirt into her pants first and make sure you remember to remove her holster then weave her bvc belt halfway through her pant loops, then attach her holster and continue pushing it through. I recommend using a plastic fork and bending back one of the prongs and using that but any pointed object will do.
Her boots have pegs in them and it took me quite a while to get her legs to snap in, make sure you wrap her pant bottoms/cuffs around her "ankles" or tape them before slipping the legs into the boot pegs.
The harness, it looks like hell with straps but it's not that complicated. I recommend removing the fewest straps possible. I loosened only one hip strap and pulled the harness down over her head with her arms raised. Another short cut which might work even better is to remove her arms from the shoulder ball joints and maybe try to just slide the whole harness over her head, don't know if that will work but It looked to me like it might.
Anyway don't think the other guys will be half as hard. I'll do Hicks next and wait for Wor-Gar to advise on how to attach the FL Apone head with the post and all.
Also the Vasquez head isn't bad at all, I was relieved they painted her hair dark brown but if you got extra bucks you may want to have it repainted...
Finally don't try to fuss with the headlamp, it is not meant to swivel. When I finished there was some other stuff in the box guess I'll figure it out later...