For fruit: Split pineapples lengthwise with sharp knife, cutting through leaves.
Cut around inside of each half with serrated grapefruit knife, leaving 1/2-inch shell.
Carefully remove fruit in one piece.
Set aside the two best shells with leaves attached.
Remove and discard pineapple cores.
Cut pineapple into strips 3/4 inch wide, then cut strips into 3/4-inch dice.
Combine pineapple, apricots, kirsch and sugar in large bowl and toss well.
Cover and refrigerate at least 24 hours.
For meringue: Combine sugar and water in small saucepan and stir over medium-high heat until sugar is just dissolved.
Bring to boil.
As temperature of syrup approaches 200°F on candy thermometer, beat egg whites in large bowl of electric mixer at medium speed until stiff and glossy.
When sugar syrup reaches soft ball stage (235°F on candy thermometer), add syrup to egg whites in slow steady stream with mixer running.
Continue beating until whites are cool and very thick, about 5 minutes.
Stir in vanilla.
Transfer meringue to pastry bag fitted with medium star tip.
(Meringue can be prepared up to 2 hours ahead and refrigerated, tightly sealed, in pastry bag.) Position rack in center of oven and preheat to 425°F.
Drain fruit well and divide evenly between reserved pineapple shells, mounding compacdy.
Pipe meringue completely over each shell, sealing to edges.
Sprinkle pineapple leaves with water and cover leaves with foil.
Arrange shells on baking sheet and bake until meringue is lightly browned, about 5 minutes.
Line serving platter with lemon leaves.
Arrange pineapples in center; discard foil.