At some point in the bus’s history a previous owner cut a hole behind the back seat row. This was probably done to bring in warm air to make up for a poorly maintained heating system. The hole was cut on an un-ribbed section of floor, making for a fairly simple patch. Prior to this repair the gas tank was taken out to avoid any fiery surprises.
Engine accessories (fan, oil cooler, etc.) taken off to make room for fuel tank removal. The engine bay has a healthy coating of sticky dust, but is in otherwise great condition.