I have just found this discussion and thought that I ought to add my part. I have owned a BrumTug since new in 1983. Boat name is Squirrel (always has been) Reg. No. 75104. I sort of recollect when we bought it from Julian Stanton and Alan Green that it was number 15 although they said that there wasn't a number 13, but this doesn't seem to agree with earlier comments. The boat is now moored on the Llangollen Canal and was previously on the S.U. Barbridge area. I replaced the original 3 cylinder Nannidiesel with a Vetus 3.10 some years ago and the bottom was overplated 4 years ago. A front cabin was added by Mick Sivewright in about 1990.
It was interesting to read that all Brumtugs seem to be surviving and appreciated by their owners.
Ceun.