I weighted 232, standing on my girl friends finally tuned digital scale this morning. She's into crossfitness, so the scale is right on. I'm a bit above 6'2 and holding a 36 waist.
With my version of the pullup, I use a close hammer grip (thumbs facing to the rear). A grip like this allows more involvement of the overhead pulling muscles. Rather than the normal middle to wider elbows out and fingers facing forward. Which, in return, allows less power/weight to be used. Each pullup rep is started from a flatfooted stance (the bar is adjusted so I only have to reach above with ease). Do not ever begin with a full or partial stretch. So, in a way, this might be considered a partial rep, rather that a true complete ROM by some. Suits my needs better, because the pullup is treated as a power movement by myself. Not actually touching the chin, as the term was used,, but to chin height each rep.
Never checked the weight of the harness but guessing around 5lbs (?). Place the two 100lb plates and two 10lb on the harness,and go from there. Set's of 2's worked very well for me last week, never to failure. The 6-9 reps was referring to a regular , non power directed, pullup workout. Weight used the last time was 150, or so
Did a search this morning and found that the official one rep pullup record is a bit above 400lbs. Not to offend, but that is so bogus, when men, past & present, have exceeded that many times (the great Marvin Eder did 8 reps, wide grip at 202bwt totaling 402 lbs...also did a 434lb dip). Those two guys (both rock climbers ...both from Australia) weighted around 150, so that extra 150 was equal their bwt. Rock climbers have the strongest pull and grips of just about anyone.
The pullup/chin is any wonderful muscle mass and power buildedr Most guy's do not take full advantage of the benefits to be gained from this exercise, also using different grip positions. Same can be said for dips. Good Luck.