Great to see another SL1K back in steam although somewhat modified.
By the way, is the loco actually named after the Welsh Solar Powered vehicle entered in the Trans-Australia October 2007 race
GWAWR -
http://commons.wikimedia.org/wiki/Image ... ehicle.jpg
Sorry I've no spare cab roof springs Graham, but they are available from Dream Steam, PPS or Chasteam.
This SL1K is running well now, so I guess it was another one with faulty cylinders or that dodgy reverser/regulator valve. Did you drill out the steam holes in the chassis frames?
By the way it looks like you could do with some deflectors on your meths burner. Although you will not melt a sight glass plastic with that boiler I'm sure the heat being let out the back into the cab would be better deflected up to the boiler. The combustion chamber rear face is cut to allow the solid fuel burner tray to be slide in under the boiler on top of the frames. So there is a gap in these Mamod/MSS locos that needs filling. On the IP Jane/PPS Janet with these boilers the rear face is extended so you do not have this problem.