For a "Bone Stock" 95 GT those are VERY good, a little too good in fact, I would venture to guess that your car isn't *exactly* "bone stock"
To figure HP #s at the flywheel, you make an assumption as far as drivetrain losses, and work backward to get the flywheel hp estimate. 15% is a very common # used for a Mustang drivetrain.
so 100% - 15% = 85% So your "wheels" #'s are about 85% of what the engine puts out, so divide your dyno readings by 85% to get your hp estimate at the flywheel.
so 219 hp / .85 = 257.6 hp
and 287 lbft / .85 = 337.6 lbft