If you have a black and white camera, I hope you can see the orange as a greyish colour and the blue one a bit darker. The you could use a tool called HISTOGRAM
Also you cold define on the same vision program two MODEL IDs
What software from Fanuc are you using ? Are you picking the parts while they are moving ?
I am using the HandlingPRO software and i pick the parts up when they arrive at the end of the conveyor. I want to check the color before the robot picks up the conrod.