(The) Mark Five

... apparently, according to this (near the bottom of the LHS):

[www.members.tripod.com] http://www.members.tripod.com/rant58/id59.htm

... had a single out in late(?) 1964 called "Baby What's Wrong", but I can find no corroborating evidence anywhere. It seems to be Mark Four with (possibly) some minor personnel changes, but I can't find out anything more than their name and that they had John Dalton in them.

Seems to be Nazareth related from what I can find.....
[www.nazarethdirect.co.uk] http://www.nazarethdirect.co.uk/history.htm
Whether or not Dalton was involved I'm not sure - given that Dalton seems to have been born & played in Southern England - this may be an erroneous assumption that Mark Five was related to Mark IV
"In a gesture of defiance, and self-publicity, guitarist Manny Charlton and The Mark Five, emulated the Jarrow Marchers by demonstration marching all the way from Edinburgh to London. By the time of reaching Market Harborough Fontana offered a “record deal”. However following the release of 'Baby What's Wrong’ Manny Charlton explains, in the end this only aggravated Jock/Sassenach music-biz tensions even more: "We made a record and came against the machine in London. The people just cashed in on the publicity we had and after the record was made we were forgotten.""

... thanks for that - I suppose it needs to be researched further! No luck finding anything out further though.