Paddle
From what I understand, to convert you have to write the CAA Ops and Law as well as AT&G. If you have more that 500 piston time (which I would assume you do), you're only required to write the law exam. You then have to, in writing, apply to the CAA for a conversion of your SAAF instructor's rating, do the flight test, send in the paperwork and take it from there.
This all changed about 2 years or so ago.
Good Luck