Seems adding, e.g. #01, #02 etc. as a prefix to each link title is the way to go for now.
Ah ok, I didn’t realise that, this was all set up well before I came along, but it now makes some sort of sense re the ACF plug-in hiding the default custom field editing, as I thought I was going crazy trying to understand why I couldn’t see the options that all these online guides were telling me to use to reveal custom fields!
Thanks, that was exactly the problem – needed to change the location rules for the field group. Actually the fact that I had to install a plug-in and create a field group at all just to change the value of an existing custom field seemed quite odd to me, how did it get a value in the first place??
Anyway all good.