Because I just did this and had a couple questions I figured I'd throw the answers up on here. JBA's instructions that come with the a-arms are pretty good. However, there's two things that IMO were missing. What to do with the washer and which side is which (they're not marked).
After putting the first one in the wrong way, I finally figured out by looking at a ton of pics online which way the a-arms were supposed to go. Looking at them initially they're the same, however, due to my superior detective skills, I finally noticed one slight difference. If you look at the ball joint, there are two gussets. One is quite straight, the other has a slight bend to it. The straighter one goes towards the rear, and the one with the slight bend goes to the front. Because pics are worth a million words, I'll just shut up and post the pics.
Note: These pictures are on the Right Front side.
Another question I had was, "Where does the washer go, or do I need it?" If you have a KK, yes you need it, and after calling Brent @ JBA I confirmed that it goes between the ball joint and the knuckle. Logically, this makes sense. If you have any mechanical skills/knowledge and you put the washer between the knuckle and the nut, you'll notice that it's quite loose, which if you've done any wrenching before you'll realize is not optimal. You can see the placement of the washer in that second picture as well. The slight difference in the gussets are circled in the pics. Hope this helps someone!
Cliffs: Bent gusset on JBA A-arms goes to the front; supplied washer needs to be used, and it goes between the ball joint and knuckle.