Class 313 handrails - 1979/1980

[Blefuscu]

Hello,

 

I am curious about the handrails on the front of the 313's. 

 

When were the shorter vertical handrails either side of the door replaced by longer ones?

 

And a bonus question... Which of the units had the large roof vents?

 

I'm pretty sure no square headlights appeared until much later (privatisation?)  

I had a cursory look at the 314/507/508s and they seem to have always had the longer handrails, and the square headlight.

Based on the images I have found my best guess for question 1 would be 1982

I think the answer to question two is 313001 to 313010.

 

I haven't found any written confirmation anywhere, just photos.

There is a note about the large roof vents in Motive Power Recognition:2 although it doesn't specify which units. 

 

I think my estimates are probably pretty close, but any solid information would be most satisfying.

 

Thanks, Michael.