Pacing is pretty individual, general guidance is slower so that you aren’t running yourself too hard but depending on the athlete “slow” is super individual.
Theres a pretty great documentary on the backyard ultra that the people who host the Barkley marathons put on, I think it does a great job of capturing the psychology of the last few standing. TLDR starting the next lap is the hardest part. https://youtu.be/ZRXKZSqvtrw
8 Laps would put you at a little over 33 miles if your using the standard 4.167 mi laps. With a marathon under your belt I’m sure you would be able to hit your goal with a similar level of training following a 50k plan.
I’m assuming the 8+ lap goal is because you don’t plan on running all night, because of that, sleep (what most people consider the biggest challenge) won’t be a concern.
So not having to worry about a sleep plan, the biggest differences are going to be
From a training standpoint I would make sure you’re getting trail miles that are going to be similarly hilly to the race course, target that zone 1 - zone 2 while training, and break up some of your longer runs into multiple short ones with 15-20 min breaks between them. If you can take a 12 mile run and break it into three 4 mile runs with short breaks you can dial in your refueling and recovery strategy and see what works for you.
Backyard ultra is a great goal and tons of fun!
Do I get the tip in this instance?
No wonder that trail is closed, I had no idea and was salty when my running route got diverted