Typical W style truss, 2X4, 24' span using 2 12's @ the bottom. Bottom of the W is 8'. I am going to use it to lift 300 to 500 lbs. If I bolt another 2X4X8' across the bottom using 24" centers for the bolts (1/4" bolts should suffice, and not drilled in a parallel line), a piece of plywood cut to fit the top 4 of the W to tie them together better. Then 2 vertical 2X4's appx 24" apart on center of the truss. Outer ends of the truss would then be the weak link, I think. Advise welcome!