We have a really similar setup! Combination of the sleeping platform you built (almost exactly the same, less than $80 in plywood) with a $200 camper shell. We leave the shell on all the time, the platform is a few pieces and can be taken out if needed. So we can sleep on top and have a few under-bed storage bins that fit nicely under the platform (Tacoma bed has a daily about 8-9" off the bottom). Nothing to set up or take down, just hop in the front and drive off! Definitely less vertical room in mine than yours.. but in the 6 foot bed, we fit me (6-3), girlfriend, and pup.
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