^^^ u asked a very valid question, an engine swap that wasn't balanced properly can put serious strain on both ends of an axle, as can too much of a drastic drop without the necessary camber kit etc. anyone who's done a little reseach before lowering should know this
ashtech wrote:they cut the mounting bracket at the base of the shock and welded it higher, 1 1/2 inches
so essentially u have a shock that bolts to the spindle with 1.5" of extra shock still below the mounting bracket? therein may lie your problem

there's the possibility of the CV joint boot rubber clamp (if it's a metal hose-clamp type) bouncing on the excess shock *shrugs* could sound like CV joint noise when u rolling in a straight line
why did u go this route anyway? u want to have to do this EVERY TIME u hafta change shocks? to hafta cut and weld brand new shocks next change interval?
a good thing to note is that any AE90/100/111 lowering spring kit will work on the AE80 with the only difference being the shock mount and maybe the mounting bracket for the brake lines
I had AE111 Levin struts and springs in my AE80 hatch and achieved a drop of about 1" all around...lower, firmer and taking load on the back without bottoming out in the rear like if the car wanna take off
try and do d ting proper nuh pallie