I am a fan of the FAST EZ-EFI system. I have the throttle body setup, but they also make a multi-port retrofit system.
Note that it will not control timing, but it does everything else simply and well. Self learning and is programmed by a hand held box, not a laptop.
FAST EZ-EFI Multi-port
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.