I have only just found this discussion so my input is a little late, but I hope of interest. The Walsworth kit (which looks like an excellent product) represents the early Sentinel CE locomotive with composite frames. By way of explanation the first CE locomotive was Sentinel 5733 that was a stock order subject to a number of alterations before it was sold to Ley's Malleable Castings at Derby. Some of the diagrams/photographs in this discussion show this locomotive. The frames were a lightweight single channel section with the section facing outwards, the spring hangers being attached direct to the bottom of the channel section and this arrangement is not correct for the kit. Following examples had the main channel frame reversed to face inwards with another, shorter, channel section mounted below. This assembly was joined by two substantial gusset plates, mounted each end of the shorter channel, the spring brackets being attached immediately below the gusset plates and this is the design represented by the Walsworth kit. Whilst this composite frame design was very strong it was also very expensive and Sentinel eventually reverted to the single channel frame facing outwards, but to a much larger section than those used on 5733. The subsequent LNER Y1/Y3's had this revised single channel frame design. Of the sixteen CE locomotives known to have been fitted with the composite frame arrangement five were sold in the United Kingdom that generally match the frame/cab dimensions of the kit, as follows -
5735 for Samuel Williams & Sons Ltd., Dagenham Dock
6007 for Aitken & Morcom Ltd., Craig-y-Hesg Quarries, Pontypridd
6020 for Dunstable Portland Cement Co. Ltd., Houghton Regis
6076 for The Derwent Valley Light Railway, York and later with Thomas Summerson & Sons Ltd., Darlington
6170 for the LNER as 8400
The last survivor was 6076 that was scrapped early 1970 after a long period of disuse.
I hope to build one of these kits in due course, but not sure which one to base it on yet!
Regards
John