Tire kits

I'm looking into a 200 mm tire kit on my 2002 fatboy. I would like to keep a sissy bar on plus the passenger seat. I've removed the 5 speed and installed a 6 speed. I've e-mailed 5 different tire kit suppliers to ask questions and get more info on the tire kits with no reply, is this stuff a well kept secret? I've read some kits just bolt on others you need a motorcycle mechanic with 40 years under there belt. I just want the best bang for my buck so if anyone has gone through this and can give me some info and the supplier that helped you out would be cool.
Thanks, Dave