For a good result you need to start slow enough maybe 1-1.5 hours slower than your road 100k PR. Being committed to the full 24 hours being on the course is the most important part. There will be a lot of lows during the day. Just keep chugging along. Run, walk it does not matter but you need to move forward on the course. Taking unnecessary breaks at the aid station won't get you any mileage.
Good luck.