Harpdog

During the mid-90s ('93 t0 96'?) Korean-made Epiphone Les Paul guitars used a Hex nut on the truss rod, not an Allen nut. It is smaller than the Gibson ones and I believe it is metric (probably 7mm). The cavity is very narrow and you will need a proper thin-walled socket angled wrench (90 degree ) to make the truss rod adjustment without risking damage to the guitar - a standard 7mm socket will not squeeze in there. The necks on these models at the headstock are very thin. I have seen some 90 degree socket wrenches with a very long socket, but these will probably not be ideal because the hex nut on the Epiphone is quite long (the nut fills a lot of the cavity) and it may be difficult to get a purchase on the end of the hex nut. If possible get a short, thin-walled angled socket wrench instead. Burring this nut will create a nightmare for you, so it is best to get the right tool before attempting the adjustment. I hope this helps others in future. ** A tool similar to the one in the link below is what you need, though I can't confirm the exact size you need. It is probably 7mm, possibly 8mm. Other Korean-made guitars (Ibanez, Jackson, Charvel) used a 7mm Hex nut, so maybe that's a clue? Truss-Rod-Wrench-7mm