lightening car
try to use the shortest bolts possible everywhere. and where strenght is of no importance use the smallest bolts you can.
its not uncomon to find 5456465 layers of paint in enginecompartments,sand down and repaint with basecoat and one layer of paint.
no slipjoints on exhaust unless needed have it all welded togheter end to end.
anything that can be moved towards the rear of the car should be moved that dirrection unless you end up with excesive wiring lenghts to do so.
brackets holding various objects can be cut down and or be holesawed or drilled with extra holes to save weight.
keep all electric wiring as short as possible.
there is millions of places to cut out wheight or just avoid adding it in the first place,only your imagination sets the limits. it all adds up .