...what's the best tactic to get the job done by someone who rides mostly flat terrain?
The Hill - It's 1.3 miles long, starts out at 3% grade and gets steeper as one reaches the summit, I'd guess it's 7 to 9% at it's worst, very near the top. 425 feet elevation change.
The Bike - Aluminum hybrid with 11-30 rear cassette and 28/38/48 crank set. Locked out front suspension fork. 700x35 tires. With fenders, rack, etc, I'll bet it weighs in excess of 35 pounds.
The Engine - 56 yrs old male, 175 pounds and 6' 3", pampered by mostly bicycling on flat rail-to-trails, 15 to 25 mile rides. Runs on regular.
I'm looking for some kind guidance. Just go at it, spinning? Take it in segments, and repeat until I build stamina/strength to go farther? Stay in the highest gear range I can for as long as I can, then drop gears? What do you recommend?