First off: Speedometer light. The bulb holder didn't come with the new speedo, so the old one was utilized. The cable had to be soldiered, the previous owner had disabled the light.
The new Piaggio (or rather Veglia Borletti) OEM part looks right from top, but that is only skin deep. I must say I was discontent with the unit; The chrome ring around the speedometer is missing. The housing of the unit is made of plastic. The holes are not threaded, this has to be done manually. Last but not least, The bulb holder is not part of the package. Not impressed.
I skipped changing the speedometer wire, but fixed the speedo setup on the front wheel. After some investigation, I found out that a part compressing the wire into place was missing. Fixed with new parts.
The old stands were replaced with new ones.
The spare wheel was beyond washing, so it was treated with a full sand blast & etch primer job. Silver paint remains.
So now the speedo works! The electrical setup however is faulty still, so no lights in the speedo yet.