== Gauge conversion == 

 Half of the Gauge conversion section is either irrelevant or just duplicates content that rightly belongs in the Gauge conversion article.  Gauge convertible sleepers do not make dual gauge, and I've seen nothing about India's Project Unigauge to indicate that it uses dual gauge (rather than just plain gauge conversion).Unless anyone has serious objections or gets there first, I shall prune out those irrelevances in the next few days.