Union setup on masterfile under council module

Hi, 

Numsa has recently merged with the NBCRFLI and all union fees are now paid through the bargaining council.  how do  I get my union code for Numsa to pull under my monthly return under the industrial module. I did try going onto the masterfile but Numsa is not part of the drop down. I then went to setup - industrial council - setup road freight but there is no option here to add another field.

there must be an easier way to do this so there are no manual merging at month end when reconciling to pay the council 

Please help or provide some guidance.