How much weight are you putting down on the legs to add mass for stability and dampening on the go766? I put a 2x12 between the legs with a 60# bag of concrete on each end. I'd like to add more but when do you worry about breaking the cast iron of the legs? I was thinking another 120# on each end for a total of #360. Too much? Not enough? I only used concrete because that's what I had, the others will be sand. I don't think it matters though does it?
I built a box using the shipping crate and put 200 lbs of play sand in it. I guess the ballast box and sand together are about 250 lbs. Been like that for several years with no ill effects. Works great.
I did same as Robert.
