Hello, I'm looking to add Interstate luggage to my 81'1100 standard. I've found someone who is willing to sell, and wants to include the huge mounting "cage" that comes with it. I'm wondering if there is a more low profile way to attach the saddlebags - I'm assuming the trunk bolts on to the stock rear rack? In any case, just wanted to see about any other mounts/attachments that might be available.