someone was asking about this last week, here is photo showing mine, SVA compliant.

bascialy 2 LEDs on a small piece of strip board with drop resistor epxoied onto top of speedo angled to shine onto the display. A small hood from milk carton plastic glued on top and covered with insulating tape.


bike speedo

You might have a slight issue with that set-up with regard to SVA. I did exactly the same and the short-arse examiner said he couldn't see the display due to the steering wheel boss getting in the line of sight.
He said if it was raised it would have been okay (ie didn't seem to care about the steering wheel spokes occasionally obscuring).

I know you passed SVA btw 02GF74(!) but others copying it might get hauled up on it....

true - it nees to be positioned so it can be seen through steering wheel. and it was but may not look it in the photo.