Mm I knew that the oredict worked on more than just ores but I couldn’t think of anything else I had changed that would have averted the error, I guess I was lucky then.
Would manually setting the item ids to a different value resolve the issue? I had to change a ton of other mod ids for compatibility between them and wondering if that could also be why I didn’t get that error. I left GregTech’s as they were though as a foundation, I don’t think i’ve ever touched your config for fear of something going terribly wrong. 
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