FWIW, I just finished the first half of dealing with a parent's finances (parent has Alzheimer's, I now manage the investments). The emotions of all this are tough on all sides, so I empathize with your attempts to fulfill his desires.
It sounds like his wants slightly exceed the reasonable expectation of his investment earnings. I'm guessing that the best course is to explain this, and prepare two options where he can see the tradeoff: "Dad, you can have $72k from the $1M, but after 16 years or so, it will run out (previous poster described how to achieve this). Or you can get a smaller amount that lasts longer, such as $6k that will probably last 20-25 years (or whatever the next option is). That's the most anyone can promise without lying to you."
I suggest avoiding time-intensive strategies such as real estate. The transition into end of life is one that raises the stakes for everyone. You should leave yourself time to deal with further changes, not lock yourself into time-consuming projects that are risky because they're not your existing expertise.
Be honest, stand your ground; be empathetic, but don't pretend he can get what he wants if that means deluding him. He may be angry, but then he is likely to come around and respect you for standing up to him is my guess. In any case, it's the last time you get to do these things together, so I suggest being honest. Even if he is upset at first, most likely the emotions will bring you closer. If you stand firm and bring real info, your role as reliable advisor will only grow.
No one can control events, of course. And few parents want to give up control. Be patient, do what you can, learn when to stop and wait (like after you have an answer, deliver it...and wait). The moments of calm waiting may soon be a needed respite.
After a while, you may find things turning out better than you ever imagined. But you will have to invest in the pain of telling the truth up front IMHO.
Forgive me if this is too personal, or my examples made false assumptions. Good luck with whatever you do!