can you guys explain to me the neg wedge kit. ive got a 65 coupe that i would like to lower in front a little more. so far i have 620# drop springs and the 'shelby drop'. but i would like it a tad lower. im probably going to cut 1/2 of a coil out and she should sit pretty good. but then ive seen guys do this neg wedge kit...what exactly is it for? how hard is it to do? ect. load me up with info . thanks