Work underway on the floor now. The seat rails added some complexity. 15mm ply (left over from the lifting bed base) glued in the spaces between ribs. 9mm insulation board glued on the ribs.
The floor is 18mm Ultralight ply/XPS sandwich, with another 5mm ply layer on top, and will have 2mm Altro over it. To fit the along rails, I had to rebate a channel, and plane down some of the packing where the van floor isn’t flat. The B pillars had to be trimmed at the bottom.
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