If imperial units are listed first, this script flips the words around to put metric first.
this script turns
into (respectively)
importScript("User:Thespaceface/MetricFirst.js");
There is an alternate version for this script that uses US Spelling standards (e.g., "Kilometer" vs. "Kilometre")
To Install that:
importScript("User:Thespaceface/MetricFirstAmericanSpelling.js");