The Hub

Today I have spent the better part of five hours attempting to get the fingerboard extension free on this guitar. I am using the method I have used for dozens of neck resets: 100 watt halogen bulb with heat shields. After a couple hours I thought I was making some progress under one corner, only to discover after some movement that my palette knife was going through the top. I then abandoned that area and have been applying heat and have tried to work the knife under other points, but I cannot even get it to start. Some notes: I did score the finish before beginning the process all along the fingerboard extension. Also, it seems that there has not been a neck reset done on this guitar previously. I am assuming that it is hide glue that has crystallized over time, however, it is behaving the way I would expect epoxy to behave. I do not want to saw the fingerboard extension because there is a crack that needs to be repaired that runs between the fingerboard extension and the pick guard. I am considering using LMI heat blanket with a caul tomorrow and try again. I am also considering using a hot puck light inside the guitar pointed upward. I do want to be cautious not to burn the guitar. I am also concerned that lack of heat may not be my problem at this point. I have performed many difficult neck resets, each with their own sets of surprises, but I have never experienced such an uncooperative glue joint as this before. Any suggestions would be much appreciated. Thank you!