Wirable cigarette lighter plug small enough to allow ashtray to close?

[comdw]

My S3 has an ashtray with a cut out at the rear that presumably allows you to plug equipment into the lighter socket and still fully close the ashtray afterwards.

I'd like to do this but the equipment in question uses a plug thats is far too big. Does anyone know where I can get a suitably small one? (tried Maplin, theirs are too big...)