Finally found this site here today in glorious sunshine (and have the red face to show for it) after failing miserably in miserable weather 2 weeks ago. This is the remains of a four-poster, with 2 of the stones still standing, one half fallen over, and one lying on the ground.
The stones sit at the end of a much later building, and one of the stones has been incorporated into the farmstead.
This is definitely a site to visit in summer (or summer weather) rather than winter. The ridge on which the stones stand is littered with stones, and if you don't know exactly what you're looking for they can be difficult to spot. However, when the grass is dry it's possible to see a very faint sheep track contrasting with the rest of the grass, and this will lead you direct to the stones (see directions below). There appears to be the remnants of a stone-marked track running past the stone setting - perhaps an original route through the glen, up away from the river and the wetter ground?
Directions - head north from Spittal of Glenshee, and after about 2.5km there is a small layby on the right of the road, almost opposite a double gate into the field on the left hand side of the road - park here. Go through the double gates, and head up the "track" that's just visible in the grass. (You should be able to see a small wooden structure on the ridge)
When you get onto the flattish ridge, turn right and follow the faint sheep track through the ford in the burn, and follow it until a second ford maybe 200 or 300m further along. Once you come up out of this second burn, you should be able to see the 2 standing stones sticking up out of other assorted stones.