One of the advantages of the overlay on a bagger is that it covers all the framework and connections between the fender and the frame. This is also a PITA if you run a tour pack, back rest or other structured items that mount to the frame.
I think I think Paul at Native Custom has some steel fenders for the rear For 'glass, Baddad has nice stuff. John at SSinister Customs has an overlay rear fender LaRosa as well has one.
The one I am using is a prototype I built with the "glasser who builds the parts for for John at SSinister as well as newly redesigned prototype bags.
Here is the mock up.
The end product has changed but I don't have pic's yet, I will try and get some today at lunch.