At last I feel I have achieved producing an Ambient Occlusion texture image in Blender, this has been a learning process for me, I have known the theory for quite sometime but using it and combining it with the multiple objects in with the Texture Atlas Addon has taken me while to fathom. Using tutorials from CGCookie I have achieved a Texture Atlas AO for the winch for the Post Apocalyptic Vehicle (PAV) project. This will help when I come to produce an AO pass for the vehicle itself. Will be importing it into Substance Painter next, my first attempt had artifacts on it as balancing the UV island spacing and baking margins is still a bit of a challenge for me.
I have now realized I am basing my PAV on a Mercedes Unimog, who knew? I have many reference pictures now on a Pintrest board.