[Chimera-users] Changing Structure/Sequence Associations by a command

Hi, I'd like to be able to change an association between a sequence in a multiple sequence alignment and an opened structure model by a chimera command. I have a model that is a multimer and I'd like to color code one of its subunits according to its sequence conservation ... but I need to reassign the automatic association that Chimera does after opening of a fasta file. Any idea? Thank you!! Best regards, Marek