Assuming that your field is named additional info:
In script step format, it looks like this:
Replace Field Contents [no dialog; YourTable::additional Info ; "WAWA" & ¶ & ¶ & YourTable::Additional Info ]
Sorry for the delay - got a little sidetracked.
I can't believe it was that simple. I guess weekends really are useful for clearing the mind.
I ended up doing an autofill and specify the field with ' "WAWA" & ¶ & ¶ & Additional Info '.
I don't know why, for the life of me, I was trying to use a Get function when I could just reference the field exactly.
Thanks for the help! Totally appreciated.