Speedo problem

[HONEST AL]

My speedo is on the fritz,lazy needle.I have a spare ,but the "as shown" kilometres on the spare is a lot lower than that on the original speedo.I cannot fathom from looking at the unit how to adjust the speedo numbers so that it shows the same as the original,i.e. increase it
If I do increase the mileage shown on the replacement speedo,is that still classed as "clocking" in plods eyes ?,or as I will probably keep the truck till it dies,am I worrying over nothing.Do I need to tell my insurance company,If I have an accident and I did not notify them of any change could they decline to cover my insurance.In reality its not a lot different than fitting a brand new speedo with zero miles,or is it ????
Answers on a postcard please,

[flounderbout]

"Clocking" is not illegal. Fraud is. So if you sell the car as having fewer miles on the clock than it really has then that qualifies as fraud. Which is bad. But if you are keeping it, or you sell it accurately described (i.e. as having higher miles than is shown on the clock) then there shouldn't be a problem.
I think it was Albannach who suggested in another similar thread taking a photo of both clocks side by side, and then you can just adjust the figures whenever necessary and provide proof (e.g. for insurance mileage declaration purposes, or when selling).
Most insurance companies operate a strict liability policy requiring that the owner informs them of relevant changes to a policy. A change of clock probably isn't a material change requiring disclosure (unless you have a limited mileage policy, in which case it almost certainly is), but why chance it? Give them a ring and ask if they need you to supply details, or send them an email or letter telling them what you are proposing to do/have done. That way if they want details you can provide them, and if they don't you have proof of what happened just in case you have a claim and the assessor kicks up about the apparent inconsistency.

[POPEYE]

when i put mine back together recently the speedo would'n go above 40mph, someone on here suggested it might be due to the needles not being pushed on far enough and the needle fouling on the glass front, they were dead right! all i did was slacken off the glass front by not fully clipping it back on and it's fine now.
i dont think you can wind on the milage as it's worked by electrickery, the old cable driven ones you could do with an electric drill

[HONEST AL]

Speedo fault

Thanks both,that answers all my questions,will give ins.co. an email and let them decide if they want more info