To put on each 10kg of 'stores' at 20% water, you'd have 8kg of sugar in that 10kg of stores.
With 2 pounds to a pint (62%?), that would be 8 x 100 / 62 = 12.90 kg of imperial 2:1
However with an invert syrup at about 73% sugars, to get 8kg of sugars, you'd need 8 x 100 / 73 = 10.96 kg of...