How do I run Meteor using NodeJS v6 LTS (or a specific NodeJS version)?

I understand that Meteor comes with NodeJS bundled as a dependency, but I have a module written in ES6 with a default argument value declared in one of the Class methods. It's currently erroring using Meteor v1.4.3.2 like so:

(STDERR) packages/modules.js:374
(STDERR)   constructor(options={format:'.json'}) {
(STDERR)                      ^
(STDERR)
(STDERR) SyntaxError: Unexpected token =

Do I need to rewrite the module to NOT use the default argument? Or is there a way to force Meteor to run v6? OR... is there a fork of a development version of Meteor that I may use for my project?

via toszter