Small batteries for coach lighting?

[ColinK]

I’ve been busy the last few weeks installing lighting in my 00 gauge coaches using Layouts4U lighting kits which are simple, easy to fit and good value.  My next batch of coaches are Bachmann Mk1s which are slightly more of a challenge.  The coupling mechanism gets in the way of putting pick ups on the bogies and the coaches are too difficult to open which rules out my normal method of putting a CR2032 battery inside.   So I’m thinking of putting a 3v battery underneath where it will not be seen in normal use. I will have a latching reed switch in the circuit so the batteries don’t drain except when the lights are in use.

 

I really want to use a fairly easily obtainable standard battery rather than one that might be hard to replace.  A CR2032 is a bit too wide to hide. Two AAA batteries end to end are just to big.  One option might be a CR1220 although it might need replacing more frequently.  All it is powering is a short length of LED strip. Has anyone any suggestions?

[The Johnster]

Stack of CR1220s in parallel hidden in toilet compartments accessible through the floors after bogie removal?