that ECU I showed you must have been off a US bike ,so not right, but for the life of me cant find a Blue/White wire, that could of been an add-on, but for power to the speed sensor you can splice that into the 10 amp horn wire

 

 

speed sensor to clocks.pdf this is the wiring diagram I used to wire the front end a couple of wires was different, but if you follow the wires from speed sensor the two main ones go to bl/r and bl/br which is the same as the wires in photo

 

still don't no where the spliced blue white goes

 

No ,I think that blue white wire should be discounted as a colour ,it looks like it could have been joined to something else, the needles dont sweep when ignition turned on

 

so if I go by the plug with the spliced wires tht would be on the left hand switch side which both black red and black brown both are grounded and get power when ignition turned on and the same happens on the same colour wires on the speedo side so do I splice going by the plug

 

sounds good, bear in mind the Pink/Green from the Speed sensor changes to Black/Red the Speedometer side of that connector

 

but if I went by the plug with the spliced wires it would be on the switch side and you do get continuity from switch side and speedo side