I used the Painless 18 circuit kit for my '67.
I love having the modern type fuse panel/fuses. One thing: Keep the half moon steering column connector. You will be pushing Painless's wires (ends already set) into it.
I found the install to be very simple.
I like the way they integrate everything onto the fuse panel; horn relays, turn signal and hazard flashers, etc..
Also, I have found, in my setup, it's very nice to have separate wires for each connection.
One problem they had a year ago, and may still be in some kits in inventory for a while: The washer pump/wiper plug wires were reversed. A call to Painless got me a faxed page with the proper wire arrangement.
All in all I am very happy with the Painless kit in my car.
'67 RS/SS w/'97LT1 & 6 Speed