I believe (my experience is limited) that you can use the Data Text Utilities Pipe which has an API call get ‘characters from left’ and then you could use an equation field to concantenate the 3 parts.
My approach to this and it may not be 100% the way to do it but hope it helps as a start.
create 3 fields to capture the trimmed values of your 3 fields and an equation field for the ID value you want to create.
Then on ‘Update Record’ you would use the pipe to get the trimmed values in to the new fields and then use the equestion fields text function ‘Concat’ to build your string.