Smith never made a model “66” in 38 spl. (At least that they ever told anyone about!). They did make a model, the number of which escapes me, for the California Highway Patrol which was the same as the 66 but was chambered in 38. The gun was stainless and had a 6” barrel with ejector shroud. It was marked “CHP” on the left side of the frame under the cylinder. CHP sold the guns at some point but before they did they over stamped the “CHP” marking so that it read “OHB”. The gun had a red insert front sight and a white outline rear and was fitted with target stocks. I think that they marked the yoke model 78 or 74 or something like that. I will have to do some research when I am near my library.