if you are going to use the Honda stem in an aluminum lower triple clamp, you will have to find a method of attaching the steel stem to the allow clamp. Most alloy clamps use steel stems, but they have a "hat" on the bottom of the stem that keeps them from pulling up thru the clamp. Your options are to weld a nut inside of the Honda stem and then use a bolt with a big washer to hold the stem from pulling up thru the clamp, or drilling thru the clamp and the stem and "pinning" the stem in place.
Tracy