Apologies for the repost but I thought it would be a good idea to include more terms in the subject line so that search engines can give more results.
These are a few points on fitting the new SIP digital speedo to the Vespa PX millennium year scooter as the supplied instructions could be better
Steps 1,2 and 3 are pretty straightforward although this is for a specific model which has AC lighting so follow the instructions for AC
The new speedo was tricky to fix into the headset as the clips look lower down when compared to the original one or maybe it was the chrome rings bevel being higher, either way you'll need to press down quite hard to hear the audible click that tells you have got it home. When pressing do so from he edges or you risk damaging the speedo 'glass', test it's security by flipping over and try it push it out again.
The wires they used feed the small bulb in the headlamp unit which is fine but if you turn your lights off you turn the speedo off
The supplied crimps or binders are designed to join the wires from the headlamp to item 3, main wire. To ensure good metal to metal contact I stripped some insulation back from the wires, I used automatic strippers so that I wouldn't have to cut the headlamp wires. You could also do this job using conventional crimps. Line up the two black wires, use the blocked off channel for the supplied black wire and the other to the headlamp wire making sure the 'blade' in the binder is lined up over bare wire and close it firmly, repeat for the yellow or live wire but join the supplied red and brown wires first by twisting together (removal of outer insulation will be necessary. These are two wires are supplied for people wanting to fit this unit to a DC model
Next up is fitting the control push button, item 5. You could just lead out of the headset to the right and stick it near the lighting control switches. I decided to utilise the electric start button. Undo the whole unit (two black screws) and it reveals a hole big enough to push one end of the push button wire through, lead it along past the throttle tube, pushing the existing wires to one side as you wriggle it through. Stick the button on to the handlebar and replace the start switch housing, you now have an unobtrusive button with no visible wires.
Ok it's now time to join it all together, I haven't attempted to join the temperature sensor, I'll wait until something else that requires removal of the fuel tank comes up.
Join item 3 to the power supply box (item 2) there is only one connector that will fit so its difficult to get wrong.
join the control button to the speedo, again there is only one connector that will fit.
Secure any fixings and tools and test that the speedo works by starting the scooter, the speedo goes through a test sequence where everything lights up and the red analogue rev counter should move with rev movement
There was no instruction to say where the power box goes so I stuffed it down as far is it would go into the cavity, arranged the wires so they wouldn't foul the headset top or bolts. Push down as if you we're closing an overpacked suitcase and attach each of the four headset bolts loosely, check to see if any wires are in the way and tighten up each bolt alternate sides to bring the top down uniformly
I think that's about it - good luck