>Strip out interior&Lighten interior
>Choose to use a massive mirror that weighs probably 5kg
Also, theres seriously minimal point in stripping out your interior that much...those plastic trim pieces barely weigh what...500grams?
You've gone to all that effort, and im willing to be you haven't touched the sound deadening(Which is where all the real weight is)
also, are you turning this into a dedicated track car now or something?