Edit Variable value in Transition?

Hey Gang,

New to EPDM admin, but making headway and actually understanding most of it  !  The situation is this... I have a transition that sends files from an Approved state to a WIP state. In that transition, the 'Revision' is changed from (example) A to A+ via Value %Revision%+.  This results in my contents of Revision being "A+".

I'm creating an "UNDO" transition, and don't know how to remove the "+" and keep the "A".  I know I can redefine/replace it, but short of having another variable (i.e. TempRevision), is there any way to remove specified text from a variable text string?

Thanks!

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