If your just loosening it, a large flat tip covered in a rag works no problem. I just smacked it with my open hand striking the driver with my palm. Took only a few seconds and didn't leave a single mark on the prelaod adjuster at all. Now if you want to tighten it, that may require a heavier blow, like a mallet. Just be sure to wrap the end of the driver with a rag so if you miss or it bouces off your not scratching stuff up.
~Mike.....
