If you snapped them off trying to remove them, odds are a screw extractor is NOT gonna help.
As stated....... soak them for DAYS..... with Kroil if you have it.....PB if all you can get.
Use a center punch...... and pound a good divot into the center of each snapped off bolt. This will actually help loosen the bolts further. Spray again with Kroil/PB for a couple of days.
Drill hole in previously made divot and THEN try extractor. It took me almost a solid day to get TWO of those things out.... I ended up drilling them out and using a punch to separate.
"For Gawd's sake, put a RELAY in there or you could burn the whole damn Jeep to the ground" ...this quote brought to you by people who do not understand the law.....Kirchoff's, Ohm's, or Faraday's.
Violation of KISS shall always ring false in TRUE engineering. - ME___
Had 75CJ5, 89YJ, 93YJ. Have 82CJ7 & 95YJ____Not one burnt yet due to lack of relays.