Peel the lemons with a vegetable peeler, avoiding the white pith.
Muddle the peels with the sugar in a 3-quart pitcher or punch bowl and let stand for 30 minutes.
Add the lemon juice and stir until the sugar has dissolved.
Add the gin and Luxardo Maraschino Liqueur or Grand Marnier, and stir.
Fill the pitcher or bowl halfway with ice and add the seltzer or club soda.
Stir again and serve in individual punch or highball glasses.