FW Spinner Advice please :-)

[typhoon_driver]

Check ebay. There are dozens of pulleys etc available.

Adam I tend to find HPC are pricey compared to others and their quality recently can leave a lot to be desired.

If you are welding the pulley onto the disc then make sure it's bang on centered.

[MattLampitt]

Thanks lads... that brings me to the next question.
How many grooves and how deep should I be looking for in my pulley system. I imagined 1 groove about 10mm deep but I really don't know. Maybe a thinner, wider belt with more grooves is the way.
And if I don't weld the pully to the disk, what other methods are there ?