Well first, get rid of crunch on Steelix because dark type moves were special in gen 3. Try replacing it with rock slide.
For Jolteon, get rid of shadow ball because it's physical in gen 3 and it has terrible attack.
Lapras is just fine
Stone Edge didn't even exist in gen 3, so throw that out and replace it with anything flygon can use.
For one of your slots I would try to use a Swellow since it's fast and has decent attack, plus it has both physical STAB.
Set: Fly, Facade, Wing Attack, (anything can go here)
And for your last slot I would put Absol. It may have a special STAB in gen 3, but at least it has decent special attack.
Set: Swords Dance, Return, Bite, (anything can go here)
Absol has really helped me with the Mossdeep Gym leaders.
Hope I helped!