You have to either keep the complete template sequence in the PDB file,
or modify the template PDB to remove the residues you don't want. An
alignment that achieves what you want without modifying the PDB is:
target: AAAAAAAAAAA-------AAAAAA
template 1: BBBB-------BBBBBBBBBBBBB
template 2: ZZZZZZZZZZZ-------ZZZZZZ
Ben Webb, Modeller Caretaker