Turning a SERK into a Road Glide could be a pretty expensive proposition. My advice would be to go to your dealer and buy a parts manual for an 03 Road Glide. The parts manual will have everything in exploded diagram so it's easy to see what you need. Basically you're going to be taking the entire nacelle apart and off the bike, adding the brkts that hold the fairin to the steering head of the frame and to the front engine guard (crash bar) and then bolting the inner fairing to the steering head brkt, hooking up all of your electicals (headlight etc) and the installing the outer fairing shell. I'm gonna guess the parts for this change will run you in excess of $2k in primer, plus electricals. I'd like to see an 03 SERG in Centennial Gold. Gilligan probably has the best example of an 03 SEEG made from an 03 SERK. One thing to look out for. When you get around to paint, the PPG paint code for the 03 Centennial Gold DOES NOT match. Your painter will need to have his supplier custom mix to your bike. For whatever reason, every 03 SERK I've ever seen is a slightly different shade. Maybe it's exposure to light in addition to the MoCo's lack of QA on their paint, but they are all different. So be aware of that. And you know it'd be cool if you could post some pictures as you work your way through this build ( or should I say rebuild )
Best of luck to you
B B