We have to replace some floor joists to meet earthquake retrofitting code. The house is single story, raised floors sitting on piers in the mountains. The joists we have to replace perpendicular to the load bearing walls and currently have 2 '2x6' boards close together. We have to replace them with '6x6' beams and then bolt them to the '2x4' interior wall bottom board. The span between each section is between 53"-68". Do you have any recommendations on the best way to jack the house up and replace these joists? Will 2ton jacks work?