Marches usually have a 2/4 time signature, but this tune is one of a number of tunes designated as a march, but carrying a 6/8 time signature. (“The Butcher’s March” is another.)
This tune is also quite often played as just a normal jig as part of a set.
It's fairly compact in the left hand, only going up to the high G on the first string, and of course even though called a march it should be treated as a jig without ornamentation, although you may wish to go the whole way and just play it as a jig, in which case you would of course include some ornamentation.
In the podcast, Tony emphasises the importance of getting the timing exactly right when accompanying tunes. Chords are G, D, C and Am.