Monster101, that noise you hear is because the drop springs are shorter than the stock so when the shock moves up and down there is a gap between the spring and shock head thus the banging sound,the same happens when you cut you spring.
you could try to tie strap the spring to the shock and put buffer rubbers between the spring and shock head, or you could just buy a sleeve type coil over which cost bout $1000-1500,These coilovers allow adjustment anywhere from 0"- 4" depending upon its application. Height is adjusted through use of a threaded sleeve that fits over your stock or aftermarket shocks and a dual locking perch mechanism.

Triple-R in San-do has Arospeed coil sleeves for $1000, not sure but i think you might be able to change out the arospeed spring and reuse your tein's since the tein's are better springs.