Alter some Images

I need an alteration to the attached picture, in that I need the 3rd colour down from the top to be changed from orange to a vibrant shade of yellow (albeit not the same shade of yellow as the 4th colour down from the top). Requirements: 1. I need the overall image to have a size of 30' (W) x 20' (H) 2. I need there to be 6 horizontal bars of colour, all with the same measurements, i.e. if the height of the overall piece is 20', then each bar must 20/6 3. All I need changing on the attached image is the 3rd colour down from the top (i.e. the orange) 4. I need approx 5 or 6 different options 5. I need the colours to be within CMYK (for printing purposes) 6. I need the file to be ultimately saved as an EPS file