I have not made an effort to save weight, but I've done some of the things you described, for example, gear reduction starter, aluminum fuel tanks and header tank, no emissions gear, stainless headers and exhaust (though steel muffler), and since my tires are bigger than stock, I don't carry a spare. On the other hand, I've kept brake boosters, I've added front vented brakes (rear discs, too, but I'm not sure they made a difference either way), the early version of Richard's twin link rear suspension is certainly heavier than the stock setup, my engine could be a bit heavier than the TC motor but my oil tank, oil cooler, plumbing is going to be heavier and I have a regular battery.
Shortly after I got my car on the road I had it weighed. It was 1660# with me in it. Figure I weighed about 200# and you get a vehicle weight a little north of 1400#. I guess you have to decide if it's worth it to get closer to 1400# for weight saving's sake.