The wingspan on the GP Spacewalker is actually 79" not 72". Taking off about 6" will probably make it easier to land. I used to think I needed a hammer to get mine to finally stop flying and sit on the ground. I've clipped the wings on other floaters and liked the results, but I think you need to use a more conservative approach - try 6" before going 12". It's easier to cut some more off later than to cut some back on. Good luck on your effort. Let us know how it works out.