I need to repair the sliding top to a serving cart that my dad made 25 years ago. It consist of two solid wood panels that are glued into a frame on three sides meeting in the middle at the unframed edge. The wood panels have split due to temperature related wood movement and the fact that the panels are glued to the frame on three sides gave the wood no room to move. My thought on repairing the panels was to remove the panels from the frame and re-flatten them. Then I would resaw the panels into a veneer and glue it to an apple ply substrate creating a veneered plywood which I believe would stabilize the panel and prevent it from splitting again. This would also maintain the dramatic woodgrain of the original pecan tops. I would like to be able to salvage the original frame but was not sure how to unglue the panel without damage to the individual components. I believe the glue he used was either elmers wood glue or a similar type of yellow wood glue. Do you have any suggestions on ways to soften the glue so it would allow the pieces to be disassembled?