just a quick question, is it possible to run gt6 and gt5u concurrently without a complete overhaul for either mod?
I had the idea just now when I was thinking about my current mod loadout.
I just tried that as an experiment (using 5.09.31 and 6.05.48), and without any changes, Forge stops me with an error message saying "You have mod sources that are duplicate within your system" (because both mods use "gregtech" as the mod id, though iirc GT6 includes a secondary mod in the same jar with id "gregapi"). Even if you were to change the mod id for one or both of them, they both do so much to world generation that I think you'd still have serious problems, and need to do something along the lines of a "complete overhaul" for one or both mods.