Gareth,
welcome back.
You don't owe me a beer, but thanks for the offer! I walked up Fingerboard spur myself 2 weeks ago with about 16kgs and it was hard enough work. I kept thinking of your attempt with the weight we all "guessed at" as I left Poverty Point Bridge and thought that I would have had a massive coronary if I had your weight on my back.
Good luck with your attempt, I know I will never complete the AAWT so I take my hat off to anybody that does (or even goes close)
Cheers,
Greg