Within series II we extend the theory of maximal nilpotent substructures to solvable
associative algebras especially for their group of units and their associated Lie algebra. We
construct all maximal nilpotent Lie subalgebras and characterize them by simple and double
centralizer properties. They possess distinctive attractor and repeller characteristics. Their
number of isomorphic classes is finite and can be bounded by Bell numbers. Cartan subalgebras
and the Lie nilradical are extremal among all maximal nilpotent Lie subalgebras. The maximal
nilpotent Lie subalgebras are connected to the maximal nilpotent subgroups. This correspondence
is bijective via forming the group of units and creating the linear span. Cartan subalgebras
and Carter subgroups as well as the Lie nilradical and the Fitting subgroup are linked by this
correspondence. All partners possess the same class of nilpotency based on a theorem of Xiankun
Du. By using this correspondence we transfer all results to maximal nilpotent subgroups of the
group of units. Carter subgroups and the Fitting subgroup turn out to be extremal among all
maximal nilpotent subgroups. All four extremal substructures are proven to be Fischer subgroups
Fischer subalgebras nilpotent injectors and projectors. Numerous examples (like group algebras
and Solomon (Tits-) algebras) illustrate the results to the reader. Within the numerous
exercises these results can be applied by the reader to get a deeper insight in this theory.
