I agree that the price for all the brackets and adapters is really irritating. That said, consider this, installing the entire kit takes less than an hour, everything fits and it is all delivered right to your door. No frustration with missing or broken parts, no "well, it looked like it would work" issues. Simple, clean and (fairly) hassle free. My entire front disc brake conversion cost less than $400.00 (including the m/c, adapter and lines), took about 15 minutes on the computer to order and bolted on with no issues. Don't get me started on the rear discs, though! The kit is the most economical way to go, IMO. Good luck.
Mitch