I'm not sure if I get the question, but if you eliminate the buckets and hardware you should only get about a 6-8Lbs savings if that.
Just keep in mind that there will be a void there after the removal and possibly create some turbulence. That area can be utilized to either install wind deflectors for more cooling into the radiator cavity or aerodynamics or both. That is what I had done to mine when I first cutoff the buckets back then.
Still can't believe how light that X is.