A yuzu does not yield much juice so I added some orange juice. The yuzu zest will more than over power the orange juice and the taste will be totally yuzu. If you're making a lemon meringue, please increase the sugar to 1⅓ cups of sugar. The yuzu orange juice doesn't need as much sugar.
High altitude bakers, don't whisk your meringue to stiff peaks. As soon as they can hold a fairly stiff peak, stop beating. Over beating meringues can flop our meringues here in the high altitudes.