Here are some pictures of the Modular Vest Strap (a modular variant of the RVS MkII sling) that Ashley (of Blue Force Gear) developed for use with plate carriers, Interceptor Armor, or even a chest rig with a rear hydration/plate carrier.  It connects low in the back by means of 2 kydex "cleats."  These cleats allow uninterupted use of the PALS webbing on the back panel and carry the weight of your weapon across the back and sholders instead of digging into your neck.  By distributing the weight of the weapon across the shoulders and back, it also eliminates the problem of the weight of the weapon pulling down the front of your rig like you might experience with a sling that is attached to the d-rings on the shoulder.  By attaching the sling directly to your kit, you also eliminate a lot of the problems with a traditional sling getting caught up in your gear when you don, doff, and use the weapon.

Attached to the back of my Lightfighter Falcon Chest Rig:
 

The front of the Falcon:
 

And a picture of it in use with a BPG Plate Carrier:

Stephen, thanks for posting.

Do you know anyone that has used this with an Eagle Plate Carrier? I'm thinking this might work well on the LE Plate carrier I'm running.

My firewall at work won't allow me to see photo bucket images, so I can't see your plate carrier pics.

Thanks.