Hello all! Wonder if anyone can help me out? Have a Remington 870 Express Magnum 12ga with a tactical stock and extended magazine tube. Want to put a sling on it. There is a holed stud on L side of receiver which accepts a standard sling swivel. Forend will not take a modified cap, due to the magazine extension. However there is an extra bracket, which holds the magazine tube & barrel together and has a hole at the bottom of it. Is that hole for a special stud to which the swivel is attached? Or is the standard practice to just slip the sling over the barrel and attach it with velcro or those black O rings? What would the hole be for otherwise? Thanks in advance for any/all info!