These two stone troughs are located exactly as described in the Canmore database, and, although the dimensions I measured (about 94 cm long by 48 cm wide) are a little different from those given in the database, these troughs are evidently the objects described here:
Link
In this photograph, one of the troughs is clearly visible under the fence, between two wooden posts, while the other one is located behind it, in a less noticeable location, directly beneath the outflow from the pipe (this pipe carries the water of the spring that is mentioned in the Canmore entry).
For views in the same general area, see
NS3678 : Tracks beside Cardross Road and
NS3678 : Track beside Cardross Road.