Wow @j.assuncao I am coming up empty. No matter what I try from your linked post or from the hass.io site example, nothing works.
Tried with {% variable %} and normal {{ states.input_text.tv_channel.state }} and a few more mixes and variations. I’m never able to pass a parameter to the shell_command.
I may respond to the thread you quoted given the action there. Thanks for all of your help.