RE: leading edge
I haven't built the UR in years but I still have that cool little LE shape template they have on the plans, I made one out of light ply because I built so many of that plane. I just used a palm or finishing sander, electric. Then I started using a small plane to remove the bulk wood, then the electric then using the template tool I hand sanded to the finished shape. Takes about an hour to get it just right.