Thanks but I've got a spaceball now
Phil never came up with the templates so I improvised. The holes are already marked on the tailgate so just drill carefully - be aware the outer holes are bigger than the inner holes - check 3 times & drill once !
The self adhesive pads initially gave me problems. These really needed to be 2mm thick but I could only find the 3Ms pads in 1.1mm thick. So for each side, I used 2 pads stuck together and it worked OK.
Initially I used single 1.1mm pads but even with the screws tightened to the full torque I could still see gaps between the pads and the tailgate.
Don't over-tighten the screws - I think I tightened to 7nm - do your own checks.
Lets' have some pics of the finished job !