TOPIC:

Does anybody have the dimensions (especially the length) of the long, bogied, wagon/truck used for the "long" 12 pr?

Wavertree
According to the "Detailed History of the Railways in the South African War, 1899 - 1902" (two volumes, this quotation from page 243), "The 12 pdr gun was mounted on either a Naval pedestal or a Land Service Mk.II mounting, firing over a three foot steel parapet. The bogie truck carrying the gun measured thirty six feet long by 7 feet six inches wide, and the pedestal was placed exactly in the centre of the floor".
Apparently there were thirteen 12 pdrs on Gun Trucks during the war. There is more information about the truck, construction of mounts, etc. on page 244.
Regards
IL.