This map is from near the start of 'Double Dukes' in season 4. It was not as clear as the previous maps and also harder because so much of it was written on by hand, obscuring the original detail. Possibly some of you will recognise it straight away - I didn't. I convinced myself that the town at the bottom, roughly midway between the two thick lines, was 'Paradise'. The highway number between 'NTY' and 'TEVILLE' is a single digit and likely to be odd as the highway is running north-south. Luckily I tried Highway 5 first which took me to just north of Sacramento. So Colonial City is actually Redding, CA. Below is the long shot with the actual map next to it.