Is it a fairly straightforward job to change over manual drum brakes to power disk brakes on a 67 or 68 bird? The kits seem incredibly expensive, do you really need the kits or can you put one together on your own? I was wondering if there needed to be something added or changed to supply more power for the brakes (in addition to changing over the brakes themselves). If anyone has done this could you send me your thoughts - was it a nightmare job, easy, any complications? Thanks!