Well, here is a start,
on an early chassis, there is not enough room to run the wiring harness behing the shock tower and down to the floor level where the later cars break through the farewall, so I put my hole above the shock tower as far over to the drivers side as I could.
You will need to run an additional fuel line for the return line.
the wiring harness is not too tough, from memory, the lines that normally would run to the front of the later model car under the seat, only has power and ground, and a fuel pump line (DME controls the fuel pump as rev limiter, so I am told)
There is one of those 14 pin connectors on the motor which normally would hook into the side pannel in the engine bay, and on my 1970 there was one that came to the same place, both of the same sex and they do not match. however I have uploaded a spreadsheet which shows that mapping on my website.
http://forums.pelicanparts.com/addictionmotorsports.com
you will also want to keep the cylindrical electronic thing which somehow converts a signal off the coil into something your tach can understand, unless you also update your tach.
that is all I can remember right now....but send me emails with any questions and I will shoot photos and answer them best I can. My car is complete (less speedo right now) and everything is working and I preserved the wiring where ever I could.
Jim@addictionmotorsports.com