D16y1 into an ED = 2 ECU's??

You shouldn't have to run two pumps. You should change the tank from the EFI car as well so you're running only one fuel pump!

I asked my mechanic to use one from an FI car, but he said its easier to use an ext. pump, so that they don't have to cut into the tank?? And also it costs about $500 extra to cut in.

the tanks I believe are interchangable - the only thing that needs to be changed is the wiring, since its electronic...

Let us know how you get on Val, I've bought an ED sedan recently and a fren wants to buy it off me provided he could turn it into a sleeper with a higher output engine ie B16A but our main concerns are the costs EFI conversion, fuel tank+pump/wiring, A/C hook up and cable clutch setup on later engines.

Mechanical fuel pumps are not intank.. how do they run if its mechanical???

clowns... ur mechanical fuel pump runs off the camshaft like every other carby engined car ever built.. You'll be running one fuel pump and it would be External unless u change the tank which r interchangable

Im going to be doing a B18C conversion on my lil ed myself (i am a mech after all) and im not gonna change the tank.. its easier just to fit an external pump.
You also need to change ALL the fuel lines to EFI lines as carbies generally dont run much over 3-4psi.. and thats after the almost all the fuel line.. They explode when runnin efi pressures.