Battery can be done easily with only minor fab. I'm running a Battery Tender unit that weighs about 4lbs, sitting in the stock location. Didn't have to modify anything on the car side, just had to fab up a few parts to install it.
Norm has FG parts.
Multiple places to get LW brakes - DDM has a kit that is supposedly a good bit lighter.
Regarding control arms...have you held one in your hands off the car? They're aluminum and very light. I doubt you get much lighter without $$$. The only reason to bother would be to get adjustable units.
For wheels you'll need to go custom to get light.
I think I already have all the easy wins;
Lightweight battery is in place (about 15lbs, I want some reserve capacity, and not need to plug in to a trickle charger every night!)
I've got TCE's brake kit, which saves a lot of mass, and the wheels on the car are fairly light, too, given their extra width.
Control arms, I was hoping for, because the front control arms are limiting my ability to go wider than 10" (and keep everything under the wheel wells), aftermarket ones might allow more clearance. Lighter would be more of a bonus.
Norm's stuff certainly appears to be good quality, and the doors and quarters are tempting, but the hoods aren't my style, and a lot heavier than I had hoped for.
This thread was more about ensuring there wasn't aftermarket support that I was missing. Looks like off-the-shelf isn't in the cards for what I want.