Not sure why I hadn't read through this thread before, but a few comments:
The inverter is on the driver's side on the Gen III (opposite side for Gen II). For this reason, I have blocked the passenger side upper grill, but left the driver's side open. My lower grill is 100% blocked year-round unless I plan to climb mountain passes in the summer. I've got Torque set to alarm if any temperature parameter gets too warm, which so far has never happened.
Make sure the head rests get installed when doing Uber pickups. They are a crucial safety component in case you are rear ended.
The rear seat is feather light. It might be 3 lbs, but I haven't weighed it.
I'll be replacing my OEM 12v battery with
this Prismatic LiFePO4 battery, which is cheaper than the OEM, and weighs only 6.6 lbs. I'm setting up a test environment to compare the lead acid charge / discharge cycle efficiency compared to the LiFePO4 before I mount it in the Prius. Lead acid batteries are very inefficient when charged at near full capacity, which is normally when they are charged.
Since the battery capacity will be roughly half of OEM, and considering the damage done to LiFePO4 when fully discharged, the LED interior lights will reduce the likelihood of draining the battery if a door doesn't get fully closed, or a dome light is left on.
I removed my rear wiper, but couldn't find the right size plastic cap to plug the hole. I just cut cardboard to stuff into the hole, and then put a strip of black duct tape over it. The black tape blends in with the blacked out portion of the window. I'll never need to run that wiper anyhow.
With the sketchy logging roads I go up, I wouldn't want the Prius any lower than it already is unless I had a way to adjust ride height with airbags. The underside is already very used, with some of the mounts holding on the front under tray completely worn away.