people buy exhaust tips, fake carbon fibre sheet, electric superchargers, 99p chips doesnt mean they work fella. that floor brace, its mounts are nowhere near were the load would be applied, and the c pillar bar, if you have a rear strut brace, its gonna do nothing, as the body will still flex side to side which is what you want to stop. the lower rear strut brace wont do anything as there is no void or weak/flex point (if anything is probably the strongest part of the starlet chassis) in the chassis where it mounts to so thats gonna do nothing apart from catch the floor and add weight.