OK, I've been busy working on the car and haven't really felt like updating the thread, I've gone through a lot of stuff, so I'll try to post this week to catch up with what I've done. Apparently you can't easily insert images into the text anymore...so now my post will just have pics at the end.
After unpacking the engine and the associated parts I wanted to modify the EROD harness to mate with the RX7. Since I was going to drive the stock RX7 cooling fans with the stock relays, I needed to take the EROD ecu's output for the fans and connect it to the stock RX7 relays.
I found out after going through the wiring that the EROD ecu sends a ground signal to turn on the fans, same as the RX7 ecu, so the extra relay I added (to turn the +12V signal into ground to turn the fans on) wouldn't be needed for the fans. Luckily though, since I was using the EROD cooling fan relay to run the starter solenoid I needed that added relay to turn the +12V "Start" signal from the starter switch into a ground signal to turn on the old EROD "cooling fan" relay which was now my starter relay. Make sense??
So I found the wires that ran the cooling fan relay (unfortunately there are two wires that go to the same relay, which means I needed to find and splice 2 wires instead of one. Once I found the wires, I would cut them and splice a wire to each side:
1) The two wires that go to the relay would be connected to the added relay which would turn the "start" +12v signal into a "ground" signal
2) The other side of the wires that goes to the ECU could be connected direcly to the ground side of the RX7 fan solenoids.
Pictures:
1) The connectors (I will splice into 2)
2) Shows the green (fan relay) wire I'm going to cut (I'm touching it with the exposed wire)
3) Shows the green (fan relay) wire pulled away from the rest
4) This shows the green wire spliced and the destription of where it goes (the blue and green wires will be spliced together later). The ECU side will be directly connected to the stock RX7 fan relays and the relay side will be connected to the output side of my added relay that turns the "Start" +12v signal into a ground signal
5) Shows the blue wire at the connector, there are two blue wires, make sure to use the one that doesn't go to the pedal (the one that isn't grouped with other wires in a braided tube)
6) Shows the pin out which shows the multiple blue wires (the bottom one that's underlined is the one we want, to fuse box 7D)
7) Shows the blue wire spliced into with the description of where each go to, same as the green wire (4).

Shows how I checked that I picked the correct wires, I put the ground side of the solenoid to the - side of a 9V battery and touched the wire to the + side, and made sure that the wire was then connected to the power circuit (and also that when the battery wasn't connected the wire was not connected to power)
I also worked on routing a thicker fuel pump wire, but after splicing two wires together (because I bought one that was too short) and screwing up the fuel pump connector (I pulled out the original wire that went to the connector, then tried to epoxy it back in, which failed) I decided to buy a longer wire and wire the fuel pump up a better way, which I'll show later.