ok heres the problem i took out the ac on my 3rd gen 3s cuz one of the bolts broke off while down shifting.
so what size belt could or should i use. ive tried like 5 different belts and they are either too long or too short or they fit but the pulley tensioner doesnt reach the belt.?? i am useing the 3s alternater some thing seems to be like only 1/2inch off.. what i have measure is that it is a 40inch every store has like 40 3/8 or 39 5/8 what should i do....

go with the one that almost fits and find a slightly smaller diameter idler pulley. that should get the belt on. but you need to make sure its not TOO tight or else you'll tear up all the bearings in your accessories.