Hi - I'm new to this Forum, so hope I am posting in the right place ...

I have a Jaguar 4 speed manual gearbox with Laycock overdrive but am unsure of which original model it might have come from. The overdrive looks very much like a C-type from a Series I/II but the gearbox doesn't exactly match the exploded view diagrams on e.g. scparts.com.

The box has a serial number starting JZN and on the main casing there are other numbers including what might be a date "13 10 66"

Any help greatly appreciated.

Paul