True-Client-IP=[12.34.56.78]

All, I have some header information coming through like so True-Client-IP=[12.34.56.78] I'd like to correct the data as it's ingested to be True-Client-IP=12.34.56.78 Dropping the "[]" from around the IP address. Not sure where to start. I feel like I should be able to use SEDCMD inside props.conf but I am not sure how that would look.