-Removing the bumper beams will not significantly increase likelihood of death in an accident. It will however increase the likelihood of something more expensive getting damaged in a small collision. think radiator, rear bodywork/exhaust/etc. A non-airbag wheel is a much more dangerous conversion than removing the bumper beam.
-As mentioned AC/Heater core/radio/antenna motor & associated wiring all will save quite a bit of weight.
-Going with an FRP or CF hood and/or trunk will save a good bit of weight. I didn't realize how hefty the trunk lid/spoiler was until I took mine off over the winter.
-there is a backing plate that is behind the plastic under-dash panel in the foot well that weighs a few pounds but doesn't really do anything.
-You could remove the carpet and discard the padding underneath and put just the carpet back in if you wanted to keep it.
-Lightweight battery
-lighter seats will go a long way
-convert to fixed headlights
-Lexan rear window if you are going to be hard-core about it. If this is just going to be a hard-parker with a braggably low weight, this isn't worth it because you lose defogging ability.
-buy a slick-top/sunroof car in the first place with no power steering & wind-up windows = ~300lb savings vs. T-Top.
-consult a medical professional to determine if you are at an ideal weight. between last autocross season and this one I lightened my "car" by ~10 lbs just by running a bit and not eating so damn much
-Drain the windshield washer fluid
-Remove the wipers (if you are in so-cal)
-I usually start an autocross event with the fuel light just starting to glow, and it has yet to starve out. Gas is heavy ~8-9 lbs/gallon or something like that.
-discard every other screw holding the bumper covers on
-completely discard the passenger seat, if you are that concerned with weight, you don't want some porker sitting over there anyway.
-light-weight lug nuts
ok, I'll stop now.