How about just tell the guy that you don't appreciate his sculpture, and would like him to put it somewhere less conspicuous?
He may say no, and fair enough, it's his own land.
That doesn't mean, however, that you cannot have your own sculpture...
I see visions of every old part that you know you will never use welded together in the throws of anguish and pain, I see the horrible reality of the human mind forever forged of steel and bad wiring, piercing the tranquility of your front lawn and screaming it's agony at the trembling souls of passers by!
And if it ticks him off, you will have one hell of an interesting art war, and a very picturesque neighborhood.:rofl:
Cheers,
Kennith