I made some Jacks for the airplane today. I used an idea I saw at the EAA 302 Tool Crib. I got three, 3 Ton Heavy Duty Long Ram Hydraulic Flat Bottom Jacks from Harbor Freight and cut a triangle base from some plywood. I used some electrical conduit, crushed and bent the ends, then used a rubber plumbing connector and some hose clamps to attach it. I was advised to use a triangle base rather than a square, as a triangle has better stability on uneven ground surfaces.