PBL made four C-18s in '84. 315, 318 and 319 were raw brass. 316 was painted (one of their first).
315 and 320 were almost identical, save for the box headlight on 320. The number plates on both engines were flame-cut steel.
318 is very close to 317. Due to the extended smoke boxes on these engine they are not good candidates for conversion to other engines. There seemed to be a lot of trading of tenders between C-class engines over the years.