They are still in right? Proper replacements in hand,some non permanent thread loc or eq. And torque specs.? For replacement time.
With proper size extractor and pilot hole i tap with light force on top of extractor once to seat it,then use small adjustable wrench to turn it . This based on assumption of an easyout type extractor.
There are others somewhere designed to engage mangled screw heads .
With a dead center hole in screw head,sometimes drilling head of screw larger than screw diameter removes head and relieves tension on remaining screw but i suspect you,ll visit smith before then.
Good luck.