(26 May 2015, 3:44 pm)Robert wrote What is the difference between the X66 streetlites to the C&C and Red Kite examples?
citaro5284 explained this previously to tyresmoke - it relates to the re-fuelling system in place at Riverside.
Note the little black thing on the 'h' in the photo below:
Go North East: 4941 / NK51OLC by Daniel Graham, on Flickr
This is just hidden away from the public eye on 5391 - 5394, as all the various holes in the bodywork don't look particularly attractive, as per the Scania L94 above.