Pete, I'm not picturing the problem very well? When you say Steel, do you mean like heavy duty angle iron welded together, now that's a man's stand :o

If so, why not let the weight of the tank & water hold it in place. After the tank is on, a few shims here & there under the legs should be sufficient to get it level. Then let the weight of the water keep it in place ... no need for the bolts?