Original sentence: When first starting in 1996, Chiltern inherited 37 Class 165/0 (Networker) diesel multiple units which were fitted with Automatic Train Protection and a tripcock so they could be used on London Underground lines on the approach to London Marylebone
Edited sentence: When first starting in 1996, Chiltern inherited 34 Class 165/0 (Networker) diesel multiple units which were fitted with Automatic Train Protection and a tripcock so they could be used on London Underground lines on the approach to London Marylebone