I swapped out my early 67 column for a 68 one, close to a bolt-in but not quite since I wanted to keep the 67 (larger) bell for the steering wheel. If you are using the 68 steering wheel (yuck) then it is a bolt-in.
I can't asnwer for sure if a 68 gearbox would bolt right in or not, but the early 67 is the same as the 65-66 and I doubt FoMoCo changed them dramatically mid-year (other than the two peice shaft). I didn't have to deal with the box at all since I'm using a TCP R&P, but I'll bet it would still bolt-in.