Will a fairing actually help with Wind resistance or is it just for looks
on a 04 XL883C
Fairings always help with wind resistance on your body. That's why every touring bike has one. They dramatically reduce rider fatigue. They also make a ride not as unpleasant in nasty weather.
There are some neat easy-off windshields for Sportsters. Maybe try one of those, first.
i have forward controls and a full face helmet and my problem is at 55mph
Part of your problem is the forward controls. With your feet forward as well as your arms, your body creates a parachute for trapping wind.
A fairing or short windscreen may help. A tank bag will also block wind to your chest without creating much buffeting to your head.
Depending on how tall you are, the forward controls may be necessary. If you're under 5'10" the forward controls may be more of a fashion statement. Personally, I dump forward controls on any bike and enjoy a more aerodynamic ride without a fairing/windscreen and just a good quality full face/modular helmet.
See if you can borrow a tall tank bag and try it out.