Round the edges of your scraper so as not to do damage the surface, then heat it when hot it will slip in the groove. Work it along only the top to create a slot, use either DeBond or Skip Sand in the groove slowly working your way down. The sealant will soften, this is a messy operation so mask off the area below. One the tip is out do your clean up with the de bonding agent. Not easy and not fun!!!!
Phil
No matter what your beliefs are "GOD BLESS AMERICA"
Fully retired marine tech near 60 years in the biz.