Back to shopping here there and everywhere to see what I could find. Finally I came up with a new duvet cover that I felt would do the trick. It had the red for fire trucks, plus new colours to work with. A girlfriend and I spent an evening "accessory" shopping for the room, I picked out the paint colours, and my revised plan/vision with squares on the walls was back in action.
We started slowly packing up his room for a few days prior to the big makeover. Thankfully my parents had J over for a sleepover so that we only had the baby to care for on the weekend we were doing the work, and this enabled us to surprise J with his new room.
Here is the BEFORE:
And here is the AFTER:
And here is what we did!
Dark Grey - (GP) Artesan
Light Grey - (GP) Spray River
Orange - (GP) Glazed Carrot
White (GP) - used to paint over the blue wall and over the trains to ensure the new colours would go on evenly