I don't think the windshield bag will fit with the 4". Here is a Tbag windshield bag on my Ultra with an 8" LRS shield. You'll probably need to go with a 6" shield. You can't really tell there's a bag there, it looks like a dark tinted shield from the front.
I Have the HD 3 compartment bags and the fit perfect with the stock shield. I now have a KW 6.5 and they work great with it also. The HD bags will match the top of the stock Shield exactly
Not sure how good it will show in this pic, but here is the HD twin pouch. I didn't care for that look too much, so I cut in half, removed the metal mounting tabs, and now use just one bag in the center (velcro). Holds my phone and glasses just fine. I'll see if I can dig up a pic and post it.