for ur handle... try looking from below.. de screw mayb hidden... or mayb got a cap or something like dat...
watch out for clips... pry(kew) with a flat screwdriver.. sometimes they stick to de panel - pull de panel out slowly with some force... if u break them.. dun worry.. goto spareparts shop... bout rm1.00 a pc..
Just wanna ask, what's the max speed that you have done with your stock Z.. i mean completely stock.. no turbocharged or supercharged.. oh well, maybe change of exhaust :p