In a saucepot, combine peaches, lemon juice, sugar, and crushed chipotle pepper. Bring to a boil, reduce heat and simmer. Allow to reduce until thick, about 30 minutes. Remove from heat and let cool in a refrigerator 1 hour or overnight.
Preheat flat grill to 350ºF. Butter each slice of bread and place on grill. Top each slice of bread with 1 slice of cheese. Top half of the bread with 2 tablespoons of Chipotle Peach Preserves and arugula. Cover with remaining slices of bread. Remove from heat and cut in half. Serve with extra preserves.