I have one of them MSD timing computers. Still in the box, on a shelf in my garage.
You are right about the weights and vacuum advance beeing removed. This isn't a big problem with a Ford electronic distributor. Just pull out the base plate with the trigger and remove the weights, plug the vacuum ports and hook up the timing computer.
The timing curve is adjusted via small screws:
Btw I think you need a MSD ignition box (6A) to use the timing computer
-Simon