40k Space Wolves & Daemons Boot Sale Bargain - Help Lawnor identify and fix please (Spring Cleaning)

This guy is currently a Dark Angel.  Most of my stuff is Space Wolves and i’d like to unify what I can.  I’m not sure how much of his iconography says that.  The right shoulder does.  Does the wings in the corner of the sape, and how about the breastplate and crotch guard?  What about the right shin?  If it is just the shoulder this would be an easy fix.  The cloak may be fixable by filing.  Not sure about the rest.

What is the unit size for Space Wolves Terminators?  This guy would be my 11th.  Would he even fit?  Or would a Captain be an extra or a solo/character?  Not sure how 40K works.

EDIT: He’s a Deathwing Terminator Captain, isn’t he?  im pretty sure I have those wing things from his shoulders.  Everything on his is Dark Angel iconography, isn’t it?  Theres no converting him I assume and I should just enjoy the model as it is.

https://www.games-workshop.com/en-GB/Dark-Angels-Deathwing-Terminator-Squad

I’m told this next guy is a Grey Knight.  Whats parts of the model mark him as such and can anything be done to turn him in to a Space Wolf, or a generic marine?  Given he is metal, and a nice sculpt, would I be better off just enjoying him as he is?  Something appears to be missing from the top of his backpack.  Any ideas?  Anyone know what the original sculpt is called and perhaps have a link to images?

This next guy looks a lot like Captain Tycho of the Blood Angels.  is he perhaps a previous sculpt of him?  Is there anything about him that ties him to a Chapter?  Should his gun have extra parts on it?  It looks like maybe the barrel is missing a piece?  There is no detail on the end there, but otherwise it looks like a fancy version of many other guns I have.

Update: He’s a Web Store exclusive from 2014 for ordering more than £50 of stuff.  he is based on the 1991 games day limited edition mini.

http://www.kriswallminis.com/2014/04/pretty-effing-awesome-space-marine.html