preserving lemons

my friend gave me a bag of organic baby lemons picked from her tree. the lemons have thin smooth skin and are tart amd juicy. i decided to use half of them to make preserved lemons and the other half to make lemon bars. for the preserved lemons, i followed this basic recipe by adding a layer of sea salt, a layer of lemons and continue repeating these two steps until the jar is fully packed. i would like to make a jar of preserved kumquats too.