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The study of the two shell system started in our first paper ``Pair of nullgravitating shells I'' (gr-qc/0112060) is continued. An action functional for asingle shell due to Louko, Whiting and Friedman is generalized to giveappropriate equations of motion for two and, in fact, any number of sphericallysymmetric null shells, including the cases when the shells intersect. In orderto find the symplectic structure for the space of solutions described in paperI, the pull back to the constraint surface of the Liouville form determined bythe action is transformed into new variables. They consist of Diracobservables, embeddings and embedding momenta (the so-called Kucha\v{r}decomposition). The calculation includes the integration of a set of coupledpartial differential equations. A general method of solving the equations isworked out.Comment: 20 pages, Latex file using amstex, some references correcte

Pair of null gravitating shells: II. Canonical theory and embedding variables