Help figure out where this phantom rust is coming from I have an object with two non intersecting UV Maps.  One UV Map (round.red.light.decal) is to place a red light decal (round.red.light.png).  The other UV Map (rust.map) was used to draw an image mask (cabin.rust.mask.png).  

I have my nodes as such...



But I have some phantom rust that I did not draw in my mask.  The face the red light is on isn't even in the rust UV map.



Thanks for any insight.  Here is my blend file https://drive.google.com/open?id=0B8ZnFrE6fxi_ZDNIanAyQ001RlE
When vertices touch on UV map, you might get stray color effects like that.
You want a little bit of space between each UV "island"  

Edit mode > Mesh > UV Unwrap > Smart UV Project
Island Margin > something small, like 0.05