Build update: Decided to add to this thread instead of starting a new one.
Had Line-X spray the high top, was going to DIY but cleanup and durability...
Floor and ceiling are insulated and complete. Went a bit overboard but still have 6' standing room.
12V / 120V system installed using one the common schematics on this site. 1250W inverter / charger and three 100W flexible solar panels VHB taped to the roof. Haven't wired up the ACR yet but the Solar is doing a great job. After modest hole elongation I made a pair of Group 31 100AH AGM's fit in the OEM frame mounted boxes but sacrificed the lids.
Sliding slat bed platform completed. 60" open and 33" closed. Short RV queen fits with a tad of trimming as it tapers to the rear. Garage below is 23" high and 48" wide. Will be adding L-Track for cargo management. Settled on 23" height to fit 5 gallon racing fuel jugs and most stackable storage options.
Next phase is the kitchen galley, upper storage and final finishes.
Just finished a 3 day trip with all the above and Dometic CFX50. Cascade Lake on Orcas Island in Moran State Park, spectacular this time of year. Being last one on the ferry, priceless!