Convert a Global activity code to an EPS activity codes

We recently moved from V3.5 to V5 and now want to take advantage of using EPS codes. We plan on tightening security access to the Global Coding and allow the various levels of the EPS to create their own codes as they deem necessary. Therefore there are several codes that exist as Global (created in V3.5) that we wish to make as an EPS code. I know we can go up the chain Project to EPS to Global, how can we go down the chain Global to EPS?
I have several codes with several values in several projects involved hopefully manually is not an option.