Some info on London Buslines here along with class histories for each DMS.D I believe was a DM modified for driver only operation, DM was one used on routes with a conductor and DMS (where S stood for standee) was a driver only operated bus from new. I got into buses whilst at university at Uxbridge and whilst living out for a couple of years our local route was the 90, which was tendered, believe to London Buslines? Mostly worked by G reg Olympians but occasionally a DMS would turn up. Think they were mostly M or N reg buses and they had about 7 of them always enjoyed a trip on them. I then realised my old school bus must have been an old DMS, was THM548N, if I remember correctly run by Castleways of Winchcombe, maybe someone could confirm?
IAN'S BUS STOP: Daimler Fleetline
Daimler Fleetline Bus London Transport: Drawings, Photos, Fleet History, Photo Index
www.countrybus.org
And here http://www.countrybus.org/DMS/DMSa15.htm
Looks like it was DMS1548