The first thing to say here is that the Register's two entries for Stuart of Bute and Stewart of Bute Hunting are incoherent and need tidying up.
The latter is a misnomer and a trade 'slight of hand'. Changing the shade of one colour does not make a different tartan, not a hunting version. I would argue that the two are the same and that technically, there is no such thing as the Stewart of Bute Hunting. It was first called by West Coast Woolen Mills in the 1980s. The STA note states that 'This change from red (to maroon) does not have the approval of the Marquis of Bute. Sample in STA Johnston Collection. Called Hunting Stewart of Bute'.
Notwithstanding my comment, if you like it, go for it. As for pleating to the red, of course it could be done but the effect would depend to some degree on the sett size. By box-pleat, do you mean an even or an overlapping box? Again, the visual effect would be different in both.
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