Early Shell Oil Can

I found this in an old abandoned barn when I was a kid. But through moving etc. I thought I had lost it. Today while clearing out the attic of my dad's old work shop, to my delight, I 'refound' this great old oil can.
I believe it is from the late teens or 1920's. I believe that this size can might have been made to carry on the running boards of early autos, but not sure. I haven't been able to find very much good info on it as to it's age or value.
It measure 10" tall x 8" x 3". It has a swivel type of spout that still works and has the Shell logo raised or embossed. It does appear that where is says "OIL" on the can, below the Shell logo, that something was painted over and the word "OIL" was added.
If any of you Petroliana guys out there know more about this vintage can, I would really appreciate anything you can fill me in on.