Access Panel

In between the passenger wheelwell and the door frame for the side door closest to the passenger door is a little access panel, just above where the floor meets the side wall. I unscrewed the panel and took it off, but there was nothing inside.

Does anyone know what that little cubby hole is for?

As I was typing this, I was thinking maybe for a tool kit or something along that line.

Any ideas?

bolts for the side door hinges live in there,,,,,,

On my 66 first gen, that panel gave you access to the interior of the side rocker panel (below the side doors)... Not sure why anybody would want access to that space though(?) I guess you could louver the inside of the rocker panel (under the van) and either pipe fresh air to the engine box or vent heated air out