Dual Exhaust on 84 with CFI

I have a 1984.5 gt350 with a v8. I had the same problem. The 1984 cars all have a low pressure pump in the fuel tank, and if its CFI it has a high pressure fuel pump on the chassis. What I did to replace this chassis fuel pump is bought a small but not too small fuel filter put it where the fuel pump was using the same lines. I believe the fuel pump connected the same way as the fuel filter but I can't remember. and I just zip tied it out of the way. Not sure if you need a fuel pressure regulator because I didn't drive it very long with the CFI setup because I switch it over to carb shortly after.

Hopefully this helps you.
 
What we did (keep in mind we were messing with SVO's putting dual exhaust on them) was to remove the rail pump (on the frame rail) and replace it with a '93 2.3 ranger fuel filter. Then drop the tank and replace the low pressure pump with a Walbro 190L/hr pump. The pump is identical to a '87-'93 replacement pump but you can get them for (I think) 160, 190, and 255 Liters per hour flow rate. Tank back in. Now you have to find/remove the resistor wire in the harness. On the SVO it was behind the interior panels in the wiring harness. It just cuts the fuel pump voltage back to the in-tank pump.

This is all going off of my memory-but I have done it a couple times and it's covered in more detail on turboford.net. It wasn't hard and it eliminated the rail pump which left more room for dual exhaust. And on our SVOs, we also got the advantage of going to a MUCH better fuel pump in the tank to supply a bunch more power/boost/fuel demand.