I will change bolts to Ti, remove: front shield, air chamber reducer, x-lock
Ti bolts- fine, 10g saved at most
Remove front shield- no way is it worth removing for the few g's saved
Air chamber reducer- what does this achieve?
Remove x-lock- I wouldn't do this. The Lefty is very active in the initial stroke for a given air pressure. It descends great but bobs a lot riding out of the saddle. If you up the pressure to make the initial stroke firmer then the mid and end stroke end up far too firm. Basically, the Lefty being active is its advantage over other forks but really does benefit from the lockout. I'd do anything to be able to lock out the fork from the bar
If you want a light Lefty then you might be better off with the 26 version then reducing the travel. The 29er adds about 100g to the comparable 26 version. The only difference would be slightly less travel but lighter as far as I am aware. If your riding isn't too technical you probably wouldn't miss the extra cm or so of travel... maybe someone can better advise with this.
I'd also be interested how to lose g's on a Lefty but I can't come up with much besides Ti bolts. Maybe a different damper saves weight but that is kind of pointless in a brand new fork...