Disc brake conversion 67 Dart

This is what I did to mine... didn't have to change the spindles or anything else for that matter. Installed it myself and works great. I went with the slotted rotors.

http://ecihotrodbrakes.com/dodge_plymouth_discbrake_conversions.html

I didn't won't to spend $1000 on front brakes but you might be wanting the nicer kits out there.