so, ever since I installed an underdrive pulley on my car (years ago) I;ve had the hardest time trying to keep my alternator belt from screeching. if I tighten it with proper deflection it last for a week then starts screeching again. if I tighten it tighter the belt stretches and it starts screeching again after a week or so.i've tried every brand of belt that the part stores sell but to no adavil. i'm about to give in and buy a stock size pulley, but before I drop a bunch of money on that, is there any advice anyone can give me, some hope to this embarrassing nightmare that has bestowed me???