How can I change the UV's on a font and then save it so that these changes are permanent?

I am working in a project that started somewhere in Unity 4 and worked its way up to 2018. 90% of the GUI in project was built using NGUI. The people in charge would like to keep using NGUI. I am having an issue where dynamic fonts will appear upside down when using NGUI labels in editor and builds. I have a hack fix that just swaps the top and bottom UV's for each character. Unfortunately t$$anonymous$$s fix is temporary and unreliable. I would like to be able to swap the top and bottom UV's and save t$$anonymous$$s out as a new font so that t$$anonymous$$s issue will go away completely, but I am unsure how I can do that.

EDIT: T$$anonymous$$s issue only happens with NGUI. UGUI renders the font properly so if anyone knows how to fix t$$anonymous$$s without editing the font itself that would be fantastic as well.

Thanks in advance.