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Whoa Nellie Deli. If you're going to hit Yosemite, it's a mandatory stop. You could even stop both ways.
Visiting Yosemite will make a very long day from Lone Pine. But then if you want to hit it first, there are spots on the Tioga Road (just outside the park) to park and sleep overnight (old road turnouts etc., N side of the road in the Ellery/Tioga Lakes vicinity)
From Lee Vining, it's a 2-hour (each way) drive into Yosemite Valley. Worth seeing if this is your one chance. Just expect the crowds, but stop at the sight-seeing turnouts, and take a side trip (2 miles) to the Tunnel View overlook (Hwy 41 toward Fresno).
If you hike in Yosemite, the Clouds Rest hike from Tenaya Lake will put you at a nice high (10k) and central point to get a big overview of the park. (You'll be looking down on Half Dome!). But it's maybe a 15-mile hike (guessing), so that plus a visit to the Valley would be a looong day.
I wouldn't use that Diamox. 500 mg, even over 24 hours is huge. Maybe call the doctor who prescribed it, and ask for a new prescription using the (relatively new) 125 mg tablets.