I had the same problem with the same frame a while back! Was worried because of the glued lugs, used a product by Ziebe (Forsch) called Black Magic, hung the frame upside down and sprayed it through the bottom bracket shell and water bottle holes on and off for 3 days letting it soak, it came out nice and easy without damaging the frame at all (: I bought a carbon post the next day
I had the same problem with the same frame a while back! Was worried because of the glued lugs, used a product by Ziebe (Forsch) called Black Magic, hung the frame upside down and sprayed it through the bottom bracket shell and water bottle holes on and off for 3 days letting it soak, it came out nice and easy without damaging the frame at all (: I bought a carbon post the next day