My advice
1.) Remove the hatch counter balance weight.
2.) Remove and replace the seats.
3.) Remove sound deadening material from the hatch and cockpit area.
4.) Do not put heavy wheels on the Z. Stay under 18lbs.
5.) Remove excess heat shielding on the exhaust.
6.) Remove and replave the under drive pulley with UR's lightened pulley.
7.) Remove and replace the flywheel with lightened flywheel.
8.) Remove the HICAS system.
9.) Replace the TTops with CParks CF replacements.
10.) Replace the stock suspension with some coil overs.