Are you sure you typed the serial number correctly?
According to the serial numbers on the ISMACS site it would be a model 15 which is not correct.
According to the break out of the catagories with in the 66 it would be a 66-1 – Redeye decals; spoked balance wheel; early bobbin winder; back fitting feet; thumbscrew stitch
length adjuster (1906-1923)- Join the Vintage Singer Yahoo Grop for more info on IDing the different types.