Had a bit of a head scratch over this one.
The pedal that you are throwing away had quite a bit of travel, compared to the hand operated master cylinder you are going to use. This now reduced travel will restrict you in the amount of leverage you can obtain over the clutch pressure plate.
So if you get it wrong, it will be as light as a feather to use, but will not quite break the drive, through a lack of travel in the handle. Or, it will break the drive but you need three hands to operate the handle. We don't do spare hands or legs!!
So a bit of trial and error will be needed, moving/changing the diameter/stroke of the master cylinder and or slave cylinder. Ideally if you could see a successful conversion already completed and just copy the important dimensions.
Had a look and found some stuff that might be useful to you.
As Peter says, you may find it hard to get parts so if you know a good breaker, keep in with them.
http://www.sacoperformance.com/proddetail.php?prod=32-1001
https://www.google.ie/search?q=BEET...wKIa3hQeSzYGAAw&ved=0CHQQsAQ&biw=1366&bih=604
http://www.rallydesign.co.uk/product_info.php?products_id=4080
Car manufacturers are now using conventional clutch assemblies as automatic units with electric over hydraulic to operate the clutch mechanism (computer controlled). So if all else fails you might consider using a button instead of the handle? But, will need a small hydraulic power pack (ABS unit?) and some way to give "feel" to the button (restrict the return of fluid going back to the reservoir may help). Giving the button "feel" will allow you to pull away without stalling.
Alternatively you may consider an electric actuator?
http://www.ebay.co.uk/itm/6-inch-13...511?pt=LH_DefaultDomain_0&hash=item27c974e01f
Now all that is not as easy as i thought appreciate all your help cheers clive ill let you all no!!!
Hope this helps, do let us know how you get on