This is one amazing build. How are you assuring left/right symmetry as you smooth the surface?
Are the thick side areas solid or are they hollowed out for things like air ducts and wiring?
Since you live in the northeast, you will need some sort of opening hatch or window on the left side, accessible from the driver's seat... or do you plan to always take all the twisty back roads to avoid tollbooths?
One thing I'd change to make things somewhat easier is the fin on top of the hatch and the ones under the back. Instead of building them up in stacked slices, change the slices to have a notch. Then into that line of notches glue fins made in a single piece. For strength concerns, laminate the fins from two thinner sheets.
The bulkheads between the battery bays could also be made that way and with a glass or carbon fiber laminate would add strength. Laminate two pieces of foam with glass or CF layer in between, then a full wrap around the outside for even more strength. That would also make glassing the rest of the battery bays easier because part of the walls would already be done, just lap the other up the sides of the bulkheads a bit.
The design would have to be modified to enable sliding in and gluing the bulkheads as that part of the stack is finished.
Really sharp inside and outside corners are a huge PITA with composite layup, especially with woven material. The stuff does not like to stay stuck into or pulled around corners. It'll pull loose and get air under it.
One fix is staples. Pull the fabric tight and staple it to the foam to keep it down over outside corners and into concave areas. How well staples work depends on the density of the foam.
A pioneer of this type of vehicle construction is Robert Q. Riley
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