The topic below may be of interest.
http://www.gscalecentral.net/tm?m=29828&high=coach+lighting
I prefer LED battery lighting as it's cheap, the lights don't flicker, and they stay on all the time with analogue systems.
The batteries need recharging after a few hours, but I don't run in the dark for more than three or four hours at a time.
Gizzy, if you want track pickup I'm almost certain you could fit the LGB carbon contacts directly into the bogie without the need for the plastic mounting piece that comes with the contact set.