Dave Rolfe, Mark Burrows, Jay Hirst, Richard Dale and I were on site today. Mark finished fitting rubber strips inside the last of the air filter frame housings, barred round the power unit and oiled the turbos. Dave carried out various jobs around the locomotive. Jay helped Richard doing an endurance test on the internal and external cab lighting in the morning, then did the same test for the entire locomotive in the afternoon. No issues were found. I refitted the cleaned and painted lid of the ETH speed valve, then marked and drilled new mounting holes for the CU5 rad fan unit in the electrical cubicle. Richard and I decided to fit that unit now, as it is at the far end of the Thin Man's passage, in the most difficult part to get at, and would be even more difficult once an air tank and associated pipework have been fitted in the same area. Some of you may recall the CU5 was made from an original by a friend of mine who is a whizz with electronics, and the heart of the new unit is a reprogrammable microprocessor. As it may need removing to tweak the program, we decided to pre-wire it and add a new terminal bar in an easier to access place, which will make disconnecting it much easier should the need arise. As the new design incorporates an LED diagnostics display we also felt it was best to relocate the CU5 away from its original position to make it more easily viewable from the cubicle walkway. I also found a place to mount a small terminal bar for the lighting timer. That unit, designated CU12, was a 20-minute timer that turned off any lights left on if the crew did not turn off the battery isolation switch. They were removed from many 50s due to them becoming unreliable. We don't have one anyway, so we are isolating the connections on a new terminal bar. The cover photo shows the now-working cab lights in the no 2 end cab of 50030 as taken by Jay.