In case anyone is still interested here's more stuff:

Another/alternative part to the song:

'Oh.Willie Macintosh, oh, Willie Macintosh, whaur left ye a' yer men?
Ye've left them in the Granes 'o' the Gauch, feeding the Cabrach swine.'

The Gauch is a farm in the Cabrach:
Ordance Survey Get-a-map
Grid reference at centre - NJ 365 245 GB Grid

And if you look slightly to the NW of that (and zoom right in) you should find Little Steplar Burn
Grid reference at centre - NJ 330 265 GB Grid

The Steplar itself is the name given to the road that passes beside it:
Mountaineering Scotland