I like kits. Keeps the guesswork out of the equation. And if it's crap, you return it and get a new one. And it's all machined already and ready to bolt up.
I agree
I purchased a kit from Tucker's, I'm pretty sure it's a P.O.L. Kit
In November many vendors offer 10% off around thanksgiving time.
I took advantage off that.
You still need to consider M/C and prop valve. Residual valves, new plumbing
Then your wheels may not fit.
The kit I used has a pretty beefy backing plate for the caliper, and its off-set.
I believe This outfit
http://www.inliners.org/buffalo/index.htmHas a kit the uses over the counter parts.