Drop the spare out to access the drain and fill bolts? Couldn't raise the body and avoid having to drop the spare? Just did the wife's 98 4Runner rear diff and raised the body up just enough by the frame to allow easy access. But still had to remove the e brake line bolt as it passes right over the fill bolt. Don't know which engineering desIgn is worse, but I didn't get all grubby doing the 4Runner diff at least.
The spare had to come off to get at the differential bolts, no way to avoid that. The whole truck was raised, maybe 10". The 2 central holes in the frame are access to drain and fill in differential just behind.
I have had the back seat out a few times. The bottom of the seats basicly lay flat real close to the floor No room for a battery. That black plastic bin under the hatch just lifts out. Pull up an edge by grabbing an edge hole bin lifts up and out. Battery in that hole on passenger side. While your in there check for water in that hatch. A lot of older Prius leak water. It accumulates in the 12 volt battery well and under the spare tire. Look in battery well I will be surprised if it's dry. Look for rodent signs,
