If I don't hit the turn signal lever/ head light dimmer hard enough the headlights turn all the way off, until I hit the dimmer switch again. It only takes a second, but a second is a long time at 75mph. How do you change the dimmer switch?

Have you ever done this kind of work?
This requires partial disassembly of the column.

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Special tools and a little experience would be worth at least seeking a couple estimates from local shops.
Call around and ask about their electrical experience. Ask about warranties and be certain to get it in writing.