You might find you save some weight by thinning out the tube from the inside.
Campy did this on some of the early light posts, pre Super Record. I found
the alloy bolts deform readily and limit my "mod" to putting a washer under
each bolt head. There is a later style lower rail that is alloy that saves a
bit of weight and also a chamfered or countersunk barrel nut, that weighs
only slightly more than an alloy one.
Stevan Thomas
Alameda, CA