Probably the first of the rubber stamped 1118s. This one has one boiler band, light in center, under the cab the motor has projection for forward / reverse switch, two ROUND top windows. Circa 1917-20. The example below came with a set that dated it to 1918.

In 1920 a new motor was added that had the reverse drum in the front.

Circa 1921-22 - We'll date these based on the tenders. Note the different lettering (tender) above and below.

Close up of  double window.

Circa 1920-21 has round top windows, lightening style piston rods, cotter pin to hold front coupler  and reverse unit in front.

The last version of the 1118 this one has square windows, gold rubber stamping, die cast wheels and a cotter pin to hold in the front hook coupler. Note the indented steam chest when compared to the other 1118s.

Not sure where to put this one, old style cab with new style motor. The cab is what you would see on a 1st series 1118, but the motor is definately later so it's a hybrid.