Re-provision/Re-configure docker-machine swarm to use consul for discovery

Hi, I’m working on a script to bootstrap a swarm cluster with consul, meaning there is no initial consul service running. After consul is set up running on three nodes that I created with docker-machine, how can I reconfigure the machines to then use the newly-created consul cluster for discovery? The only thing I can figure is to modify the json config files in ~/.docker/machine, which seems sub-optimal/hacky.

Editing config.json and re-running docker-machine provision is the only way today.