Yeo -- I managed to dig up a google cached version of the old maximum muscular bodyweight calculator found on weightrainer.com
Anyway, you didn't post your ankle measurements, so here's your maximum muscular bodyweight at 8% bodyfat, 5'9", 6.0 inch wrists and several different ankle measurements:
ankle: 9" -- bodyweight: 180
ankle: 8" -- bodyweight: 166.8
ankle. 7" -- bodyweight: 155.2
So just interpolate your bodyweight from those. As to the accuracy of the calculator, I think it's pretty good. The guy who came up with the formula applied it to the known measurements of all the Mr. Olympia and Universe winners before drugs started being used. The maximum error between their actual weights and his predicted weights were 1.6%.
Side note: the biggest of the olde tyme bodybuilders was 225 pounds at 6'1" (Reg Park). Kinda makes you suspect a helluva lot of juicing going on nowadays.
-casualbb