Help identifying a Regiment please

[MacRob]

My old eyes are struggling with the picture and if the kilts have no tartan pattern, then I wonder whether the London Scottish might be a thought?

There is a sett in the tartan so it is not hodden grey. I tried to scope out the badge but there is no detail, of course. So, got out John Gaylor's book on badge collecting and leafed through some of the Scottish regimental badges. It may be Liverpool Scottish, if that is the badge on the cantle of the sporran. It was the only one which seemed like it would resemble what is in the photo, with limited detail. But they did wear diced bonnets and these chaps do not.