LED taillites

[Brian]

I wrote a coupla years back about how my 35, equipped with LED taillites [the multi-cluster type ones mounted on a panel that fits within the confines of the taillite housing], even when turned off, flicker in time with the idling engine- rump, rump, rump; blink, blink, blink. I put that down to them picking up EMF off of the HT leads. I 'think' it was Murre, suggested I fit a resistor? [Where is Murre?- haven't seen him post for a while]....
Anyway, I digress. It has now been drawn to my attention that the taillites are on at all times; very faintly, probably one candlepower? This was first brought to my attention last week, on a terrible wet night....I figured there must be some parasitic draw, with everything being so wet, I thought possibly stoplite switch or similar was wet enough for a bit of stray current to leak through, sufficient to ever so dimly power the LED's.
Today, [a fine day], I have investigated to no avail; disconnecting the brake lite switch had no effect, so I dismantled the light switch, cleaned it thoroughly with contact cleaner, blew dry. No difference.
The draw doesn't register on the [dash] ammeter. Doesn't blow the fuse.
There seems to be a slight leak somewhere....
Where to from here?
Car is 35 sedan, converted to 12 volt, neg earth, running all original type wiring, three brush gene, etc. Stock as , apart from the voltage change.