George Whale had rebuilt 26 of the Class B compound 0-8-0s with the addition of a leading pony truck between 1904–1908 to what would become Class E in 1911. However, from 1906 10 Class Bs were rebuilt with larger 5 ft 2 in (157 cm) diameter boilers, along with a pair of Class Es (Nos. 1038 and 647) in 1907 and 1908 respectively.
From 1921, the LNWR started rebuilding the Class Fs into Class G1 superheated 0-8-0s, and by the grouping of 1923 six had been rebuilt. The remaining six were allocated the LMS numbers 9610–5. The LMS rebuilt a further four into G1s between 1923 and 1925. The last two were withdrawn and scrapped in 1927 and 1928 without being rebuilt.
Baxter, Bertram (1979). Baxter, David (ed.). British Locomotive Catalogue 1825-1923, volume 2B: London and North Western Railway and its constituent companies. Ashbourne: Moorland Publishing. ISBN0-903485-84-2.
Further reading
Bob Essery & David JenkinsonAn Illustrated Review of LMS Locomotives Vol. 2 Absorbed Pre-Group Classes Western and Central Divisions
Edward Talbot, The London & North Western Railway Eight-Coupled Goods Engines