We started with an 80″ long bed, but it overhung the bench seat too much. Cutting it down to 73″ is still very workable and makes the bench seat comfy again.
We bought our bed panels from Overland Sprinters. They are partially DIY – you get to add your own wood top to the aluminum frames. We extended the wood top on ours by 1-1/2″ each side on the two front panels and 1″ each side on the rearmost panel.
That gave us a regular queen bed length, but unfortunately it also meant that the bed overhung the top of the bench seat. Sitting in the seat was almost impossible.
We cut the wood panels back to be flush with the aluminum frames. Because we’d already made all the fixing points in the wood, the easiest way to trim them was using a router with a flush trim bit. The bearing on the bottom of the bit runs along the aluminum, and the blades on the bit cut the wood down to the same position.
Now the mattress is a little bit longer than the bed – and we’ll probably cut it short too – but the platform is still long enough for both of us to sleep on comfortably. We might even buy sheets that are specially made for shorter beds – they’re called Short or RV Queen sheets.
Most importantly, we’ve got back the use of the bench seat. We put a length of pipe insulation (the foam noodle stuff with a hole through its center) along the front edge of the bed platform to make a cushion. It serves very well instead of the headrests.