unless you have a nipple for a grease gun (i can't remember if the bbk's do or not) you have to remove the control arm, remove the bushings and use silicone grease on the bushings.
BBK's do have zert fittings. Get yourself a grease gun and a tube of grease and lube them up. They will quiet down. I would lube them every oil change, or as needed. They are noiser in cold weather too....don't know where you live, but here in Detroit, it's only 30's....
My front end squeeks as well after I re-did my suspension. However, I used Ford control arms and there is no grease fitting on the ball joint. I replaced pretty much all of the bushings in the front with polly bushings. I assume this is the cause of the squeeking? I remember people saying that polly bushings are loud, does this sound correct? It is kind of annoying when going over speed bumps