I haven't seen many Heintzmans, Roger would know better if they had a model which needed the stretcher removed. I'm sure he would have mentioned it rather than removing the glued and doweled keybed. More often on some older American makes and recent Asian makes, the action brackets expand causing this type of binding. Hammer blocking is a symptom. Look for cracks in the metal. Since you removed the glide bolts as suspects you may have to cut the front of the brackets. Hopefully, as you said, the frame might relax enough to spring it down to coax it out but that probably would have been possible initially. Good Luck. Regards, Jon Page
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