Don't go completely mad with the eating in the evening. If you're doing 4/5hrs riding a day, and eating during the ride, you won't need much more than recovery food/drink immediately after and and normal-ish meal in the evening.
During the ride, eat every hour - something about the size of an energy bar, but it can be whatever supermarket food you fancy. If you start to feel your enthusiasm for the ride go, definitely eat a bit, that's usually your blood sugar dropping before your stomach feels hungry. If it's hot, throw in some electrolytes during the ride, or immediately after to rehydrate. If you keep yourself topped up during the ride, recovery is a lot easier.
After the ride, recovery drink or some lean food within 20 minutes of finishing is best. Then a normal meal afterwards.
Having looked around at other riders during Trans-Wales, it was the slower riders stuffing their faces with 2 heaped portions of dinner every night, trying to make up for lack of fitness and just making themselves bloated. The quicker folk ate substantial, but reasonable amounts.