Most Giant Scale planes weigh too much to be supported at the fuse--- and the wing is not built to support the weight or the psi. required for a 1/4 sq. in. or less, probe on the bottom. What ever you used, finger, pad, ect. would poke a hole in the wing.

If you do not have help avalable, tape a hardwood triangle on the wing tip at the CG, then place the plane between two tables, chaires, boxes, whatever, with the hardwood triangles on the wing tips supporting the plane. I fly 33 and 40% planes and I use cheap automotive jack stands. If you use jackstands you can keep the plane close to the floor where you can controll it and move things around without having to reposition or worry about it falling off something.

my .02.