So I see you have discovered one of the real issues with high abv beer, the heat that goes into the wort.
I have found that its hard to get above about 6.5% and keep the temperature below 30 deg C where you will risk killing the yeast.
Skills with blocks of ice, cold water baths and even a fridge start to become needed, or go the whole way and invest in a cooling coil.
Whichever way you go, making a decent RIS at 9-10% is more than just popping 3 kits and some 'kilos' into the fermenter.