Hopefully, possibly, this ultra challenge will light a spark in Mr. Hall, and he'll realize that he still has a love for running, and it will remind him of a dream from long-ago that he has been suppressing. This ultra will shake the dust off that suppressed dream, and he will become enamored with mulling over that dream once again, asking the questions, "Is it too late?"; "Is it still possible?"
That dream...was to break 4 minutes in the mile.
Should Mr. Hall take the next step, and ask the question, "How would I even start again?", I recommend he read my comments in the thread titled, "20 minutes 5k training":
https://www.letsrun.com/forum/flat_read.php?thread=10128267
In that thread I describe a training protocol backed by scientific studies: "4x4 Interval Training"
https://www.youtube.com/watch?v=1XDsRNeVynk
4 mins on, repeated 4 times per session, with 3 sessions per week. Replace the lifting of heavy iron with these 4x4 sessions, Mr. Hall, and whittle that power down to a honed racing machine. You can always bulk up again later in life, but your God given talent to run fast will only last so long.
It could likely take a year. Twelve 4-min reps per week (spaced out over 3 sessions/week), performed for 52 weeks, is a total of 624 of the 4-min reps, run at 90-95% HR max (as I discuss in the other thread). The treadmill speed/incline is incrementally increased as your fitness builds, and your excess weight comes back off.
Should you complete the task, Mr. Hall, and come to terms with that dream's 'unfinished business', your legend will be sealed bigger than any off-the-shelf running drama, (e.g., "Once a Runner"). It will be an apropos conclusion of the Final Chapter of "The 41st Day."
God bless whatever you choose.