Define your own labels for the User Defined Fields on the Customer Address Maintenance window.
(Microsoft added this feature to Dynamics GP in GP2013. See Tools >> Setup >> Sales >> Options)
Navigation: Tools >> Setup >> Company >> Setup GP PowerPack
Mark the box next to TWK-RM: Customer Address UDFs*.
This Tweak requires additional setup. Double-click on “TWK-RM: Customer Address UDFs*” to open the Tweaks Setup window. Locate the RM: Customer Address UDF Labels section:
Enter the desired labels, then click SAVE. Close the GP PowerPack Setup window.
The feature will be enabled for the current user. Other users must restart their Dynamics GP client to enable this feature.