Thanks to another thread, I have overwritten the ".pbos" files successfully. I'm not to sure what it asks to do with the "ctab" "@506th" and "@ACE" folders though. I will post the instructions that were given by the "506th Mod Pack" below.
"Ensure RHS is version 0.3.7 BEFORE doing the following:
-Delete and completely replace your @506th folder
-Delete and completely replace your @ACE folder
-Overwrite the following .pbos in your @RHSUSAF addons folder:
rhsusf_c_troops.pbo
rhsusf_c_a2port_armor.pbo
rhsusf_c_rg33.pbo
rhsusf_c_a2port_air.pbo
rhsusf_c_heavyweapons.pbo
-Overwrite the rhs_c_weapons in your @RHAFRF addons folder
-Replace your ctab userconfig - Don't forget to change the keys back to custom keys if you had them changed(you can do this in game now)"
Also, what exactly am I supposed to do with the AiA Patch?