911 - Ive done similar trips on my 950 with the gobis and stock pipes. By shedding the cans and gobis, going to the GPR and soft bags ive saved just under 20kg that was dead weight. The tank will be carried forward and low and being linked - centralised which shouldnt have an adverse affect on handling. As for how much you take "camping" well thats a self inflicted tax that Ive got down to about 12 kg total.
What Im saying is the tank will carry fuel when needed and when distances dont require it - they'll be empty. I'll be keeping the rear luggage plate and handles - maybe a semi custom rack to keep the bags out but the tank is a better bet than jerrys or other slung on up high.
Might even get me a set of those safari's and have near 70 lt of fuel for - well I dont know what but it sure would be a long way between fills.