reflectors have to go. that's free
take things off and weigh them
Find out how long the BB axle is, and try to buy a chainset to suit. It'll probably be around 113, which gives a wealth of good shimano options. Aim for Deore LX as a minimum. it'll have much lighter arms and alloy chainrings for potential savings into the hundreds of grams.
you will NOT save large amounts of weight on derailleurs etc. the best places to save weight are on parts that are large areas of metal.
oh and that saddle has to go, if not because it's heavy then because it offends my eyes
dont buy a bolt kit at this stage!