Drill screw heads out. Remove tracks. Use vice grips or similar locking pliers to bite down on threaded shafts and spin em out. Or use a grinder to cut a larger groove into the screw head and use a big flathead or cut a large cross into the top and use and no 3 philips screwdriver to remove them.
If the screws are pan heads you might be able tilo bite onto the lip with a pair of locking pliers and forgo tge grinding/drilling/etc.