If you are getting the complete engine with intake, carb, etc., then all you will need to buy or make will be a transmission crossmember for the AOD. Frank aka 71Gold makes them for this swap.
A few of us are running 5.0L's with AOD's already. Any questions, I think we've all got it figured out. Mine is column shifted using a Lokar kit and their TV cable, with Doug Thorley shorty headers, and Franks transmission mount.
The one I'm looking at is EFI out of a truck with the AOD tranny attached. My car was column but I've moved it to the floor. I'm using a 6" lokar shifter with an adjustable shifter rod. How difficult is it to drop engine and tranny in at the same time, and would my headers work?
You'll also need to replace the truck oilpan with a front sump unit. Your headers ? That depends on what headers you're using. The AOD is wider than a C-4 in the pan area, It also has a bigger bell and flywheel (164 tooth) that will cause issues with most headers, unless you have a set made for an FMX application. You will also need to install a high pressure fuel system to feed the EFI. Finally, there's the driveshaft, you can use the AOD's slip yoke and a combination U joint to mate it to the driveshaft, but that's assuming that your driveshaft doesn't need to be shortened first
keep in mind the 80's truck motors do not have the roller cams like the mustangs do. and look into a constant pressure valvebody for the trans to eliminate the tv cable