Reinstall node using nvm on OS X without removing node_modules?

Following the latest advice I decided to remove a previous working Homebrew node install and use nvm to install node instead, and also set things up to avoid using sudo.

However, before going further

I carefully cleaned out the following folder (owned by my user) except for two modules used for a long-standing Ember project that uses an older version of node (because I'm not confident of reinstalling the required version of them later):

/usr/local/lib/node_modules/
  bower
  ember-cli

If I keep the existing /usr/local/lib/node_modules/ folder with the versions of bower and ember-cli, will this cause any issue on installing nvm and then the node versions I need?