49th West Riding Black Watch

[Blaidd]

I just unrolled some of that tartan to begin thinking about making a kilt for myself - was doing all sorts of considering.
Looking at the photo I see that I have one of those canvas belts - but it is part of the battledress.
There is no centring of the set on the apron.

Anne the Pleater

Anne, if I have understood you correctly, you will need a 37 pattern webbing belt (the latter 39 pattern was specific use and made of leather). Alternatively, a 58 pattern is quite similar, although more olive green in colour. The Battle dress belt is as you correctly state, attached and sits to the right hand side generally. This is to deconflict with the buckle on the web belt.