Front Sway Bars

I am new to this site and any help would be greatly appreciated. I am recently finishing up my 67 barracuda conv. and I am in desperate need of some help. I converted the front brakes to 74 duster disc. These are my questions:
1.What is the difference between polyurethane bushings and polygraphite?
2.I did not switch the lower control arms. What will I need to do to them? I heard I might have to move the sway bar tabs? Or do I need to convert the lowers too?
3.Does anyone suggest any specific company for the bushings and sway bar?
Thanks