What do you need to know?

You either need to have a custom EFI manifold made (best overall choice), use a TBI setup (adequate choice), or modify the head so you can use a 22RE manifold (probably a compromise choice. The fuel maps and advance tables are short work for a professional tuner once you get the rest of the conversion in place, but yeah, no one makes a complete off-the-shelf EFI solution for a 20R head.

Actually, if you don't need to use a plenum for forced induction, you can use TWM's individual throttle bodies and a Weber-compatible dual sidedraft manifold:

http://www.twminduction.com/ThrottleBody/ThrottleBody2900-FR.html

They are admittedly pricey, but they are supposed to be incredibly responsive.

You still need the fuel and spark management, but the TWM EFI solution would get you linkage, manifold, throttlebodies, injectors, TPS, etc.

-Jeff