I have managed to strip my Dyson and to remove the actual clutch and can now see no way to dismantle the actual clutchin order to get a new belt rond the white spindle
Thats completely wrong answer,
The Dyson range of machines that have a clutch both belts can be replaced by the owner all you need are a few tools which are readily available from any stores that sell tools.
Two new clutch belts available from any good independent vacuum repair shop (poss only UK)
And a repair manual readily available on Ebay.
I know this because I did just that & saved needing to have new clutch fitted by repair shop.