Alright, I have seen the thread that never ends going on and
on and on.  Now I must break down and add to the list:

Huck and the King of Hearts (1993)

A split window bus plays a central role because it spends
the entire movie with the rear end up in the air.  Judging
from the back-up lights (one year only on splits) it is a
1967.  At one point the lead is under the engine asking for
tools.  Sitting on the rear bumper is an oil filter, so I
guess the PPO (the worst kind, I hear) added an external
system.

-Jim Bryant