Thank you all for your posts. 
After making it my mission to get this sorted, I spent the afternoon tracing all the wiring I have done and in the end it turned out to be the Distributor pick up coil. Luckily I had one in stock so fitted it and she fired right up on the button again. Just need to wait for it to stop raining now and we can get out and about.

I have double checked the wiring again and it is all good. I checked for a live to the coil and that is good. I changed the TFI module for a tested one but still no go. I am awaiting a new coil and distributor pick up as the engine always started straight up with no problems and ran sweet. The code 14 threw me a bit but I have rechecked and that code no longer comes up. Obviously there is no spark which is the cause of the problem. Im hoping its a coincidence and that the coil just happened to go out as fitting the resistors was very easy. If I change the coil and still no go, I will disconnect the resistors and see what gives.

Thank you all for your replies.
 

Thank you both for your help.
 

So I finally have my 66  EFI running lovely with the new gauges in the dash. Its time to take it to get the steering alignment set up but I just went to connect the TV cable to the throttle linkage and see that I need to make up some sort of bracket as if I just connect it the the linkage, the tv cable will stop me getting full throttle. Anyone got a pattern for a bracket or picture of where to connect the TV cable? The TV cable I have is a Lokar cable.
Thanks for any help.

I have wired my VSS, which is a Ford E9TZ-9E731-A, into the ECU of my EFI install. Doe it matter which polarity it is wired into the ecu as it probably just sends a signal. 
Secondly, I am installing an auto meter speedo which uses the same signal but it says to use the high signal from the VSS but only shows as using the high side and not the other terminal. Does it just need the high side signal and earth to make it work?

I take it that the "High side" is a positive.

Any help very welcome. Thank you.

Thank you for your help. All noted and connections made accordingly. The Bap sensor does have a collar on it and will not be connected to the manifold. I am not running an air pump on the vehicle.

Thank you all for your information. 
I feel fine to fire it up now.

Thanks for your responses.
So today I checked the actual Firing order of the engine by turning it over by hand and manually feeling the compression coming up. It is a 5.0 HO with the firing order of 13726548.

The ECM that I have is an A9P but the original ECM which I still have was an L1C.

The old distributor ( F0SE-12127-CA) had seven wires coming out of it into a round connector and a remote TFI as you said Bob. I think that previously we said that the ECM and loom was out of a T-Bird.I did see this engine run and drove it when it was fitted in a Fox body with a three speed auto trans and the engine ran beautifully

Other information:
I believe that My wiring loom is a Factory Five  RJM wiring loom which states:

• The distributor should be specific for your engine (5.0L / 5.8L) and have the TFI Ignition Module mounted onto the side.
• The harness is set up for a “High Output” firing order of 1-3-7-2-6-5-4-8 in its stock form. Your camshaft and computer should match this firing order.

So theoretically, this should run ok??

•  

Is it ok to run a TFI distributor on a 5.0 HO engine. I assume that I need to change the camshaft gear on the bottom of the distributor. 
Also, if the EEC is not from a HO engine, is the injector firing different to an HO engine?

I saw a clip on youtube saying that you cannot use the TFI distributor on a HO. I am just about to get my 302 EFI and AOD fired up and now im thinking, is this ok.
Any help greatly appreciated.


 

What hoses are those that have the 5.0 HO EFI engine in their 65/66 Mustangs using?
I have sourced a top radiator hose and I assume that the hoses from the water pump to the thermostat housing and the heater pipe are standard. The hoses that I am struggling with are the Bottom hose for water pump to radiator ( on the left hand side as seated in the driver seat ) and the hoses from the heater box to the flow and return heater pipes on the engine. Other than that, I still have to make a mount for a Gas pedal and I should be good to go. Its been a long journey and thanks to help from lots of you, especially Bullet Bob, I have enjoyed the experience.

Hi, In the final phase of the 5.0 conversion in my 66 coupe. I am running nylon flow and return lines but not sure if to run them where the original was for the 289 but seems the only (somewhat) protected option. Also interested where anyone ran the battery cable now that the battery is in the trunk and did you run both pos and neg to the front?
Any advice greatly appreciated.
Thanks.

Thanks for the reply. Please could you be more specific as in what is Midlife?
Thanks.