I do not like the idea of compressing the springs to get a stiffer ride or cutting out a section of the spring. Your best bet is almost always to get a performance suspension spring set. Depending on your year Vette this will lower the suspension between 1/2 to 1 inch. You will need to get an alignment after installing a kit like this because it lowers the car and changes the dynamics of the suspension.
Such as this to improve the handling of the car. It is fairly inexpensive and a better solution.