I have lost the key on our KX63-3 digger, i have a red key that apparently is used to code the black keys? Is this the key i need to order from you? The machine is 10 years old.

I have had a look at that key for you and it says for this key that it suits 3rd generation '-3' Kubota diggers without coded ignition. If you have a key that is supposed to code the others this does not seem like it would be the right one for you. Do you still have the manual for your machine? If so it might let you know the code for the keys you need.