I've managed some time to come back and update my core mods. They now come in the form of packaged game pcc files. You use them to replace the original game pcc files and then update your game and DLC pcconsoletoc.bin files with ME3Explorer. Instructions in each package.
Brings an ME1 heavy armor, type HVYa, to ME3 along with an ME1 urban camo pattern. Replaces the Cerberus Ajax armor in the Alt Appearance Pack 1 DLC. More texture options to come (including Colossus).