Thanks guys - I did get a piston winder for £17 quid in the end - i'd rather do it properly first time for that price - although making 'special' tools is fun!
Snipe nosed pliers and a piece of wood with some holes cut out does the trick apparently.
£17 is nowt really though for the tool, I had to pay £32 for mine as I forgot to pick one up from GSF when I bought the pads. I hate buying things from Halfrauds its like admitting defeat!