When first introduced 21C101 to 21C163 had the original Bulleid style cab with narrow front lookout and two large side windows, the rear one of which slid forwards behind the front. Complaints were made due to a restricted forward view, not helped by the position, inside the cab, of the vacuum ejector controls, in front of the window on the driver’s side. Therefore starting in July 1947 the cabs were modified, with a wedge shaped front (sometimes referred to a ‘V’ shaped) giving a larger front window area. This resulted in a slightly smaller side window area which was then fitted with three windows the rear two of which slide behind the front to give in effect the same open window area as the original style cab.

The Hornby Light Pacific models all have the modified cab arrangement which restricts the of prototypes that can be modelled in either Southern or early British Railways Liveries.

To suit my own modelling period on Fisherton Sarum of 1946 to 1949 I have therefore modified a number of my Hornby Bulleid Light Pacifics to the original style cabs.

This involves cutting of the Hornby cab moulding, quite a daunting task on a £70 / £80 or more model, and replacing with either a scratch built brass cab, the Nickel Silver etchings from RT Models. or utilising replacement cast whitemetal cab sides that are now available from the Southern Railway Group (The production of these was prompted by my original conversion being detailed on the SREmGsite). After fitting the new cabs I tend to repaint the entire locomotive using either Railmatch or Precision Paints aerosol malachite green and number and lining transfers from the Historical Model Railway Society.

As well the change in cab styles there also a number of different length smoke deflectors fitted starting with the original short length that then were increased in length to the standard length, whilst the three class members assigned to the Locomotive Exchange Trials in 1948 were all given extended deflectors, which they kept until either withdrawal or rebuilding, Note these three locomotives also received the wedge shaped cab prior tot the trials too).
Further information and a step by step process can be found on my Talking Stock #7 post here or the Southern ‘e’ Group (SeMG) site here or my RMweb blog here

Whilst on the subject of cabs it should also be noted that the last 40 built from 34071 to 34110 also had wider 9′ 0″ cabs (wedge shaped from new) instead of the earlier 8’6″ width.
A good summary of the basics. Now that you’ve done all this work Hornby are more likely to release an original cab light Pacific. 😉
Well I have been doing this modification for a few years now, the first one I did was on a pre china super detail Light Pacific which also benefited from the additional detail from a Crownline detailing kit.
This cab version has been mentioned to Hornby on a number of occasions but I am not holding my breath.
Graham, your original cabside Bulleids are great, I will be taking this approach to a few of mine. Its been 20 odd years since Iwas an SRG member, must rejoin in the new year.
Hi Alan
The SRG is well worth joining. Thank you for your kind comments.
By the way, I spotted Barnstaple during the 1948 Exchange trials on the midland main line at Desborough, Northants. Thanks for all your hints and tips.