Saw the ad (Sporty's? Spruce? Somewhere) about the ABS box that holds
oil, spout, tools, etc. $140 or so.

Back to the local hardware or household store. RubberMaid box (with
top) for $10. Holds minimum tools, roll of paper towels, quart of
oil, landing light, gloves, strainer, tie-down ropes. Goes into
the corner of the baggage area.