I've been looking to do this to my EF Fairmont for a while now. Pretty straight forward if you go about it the right way. In a nutshell you'll need the following major components:
1. Engine (obviously)
You can pretty much use any 5 Litre windsor from the EF/EL family. It might be possible to use an AU V8 but can't remember is any of the electronics differ. Even if they do, i don't imagine it would be too difficult to convert these specific components back to EF/EL ones.
The main guts of the auto in the 6 (93LE) is identical to the 8 (97LE), however the bellhousing and output shaft is different. Keep in mind the auto in the 8 is controlled by a seperate TCU (Transmission Control Unit) thats located on the side of the pedal box, whereas the TCU for auto in the 6 in integrated into the engines ECU.
I suppose the above really doesn't matter if you're converting to manual.
3. V8 Engine Harness and ECU
Being a Fairmont Ghia you'll also need a high series V8 engine harness and ECU. Replacing this involves removing the dash.. You'll also find that Ford don't sell these brand new so if you'll have to buy a smashed wreck or a conversion kit from a wrecker.
In addition to the above you'll need power steering lines, water hoses and everything else that i've forgotten to mention
. Its a damn big job and it'll soak up more than a few $$.