I just did the eaton swap on my 01. Its a great swap. You will pay $2000 and up for the complete package. You may need the 99+ heads to do the swap. The heads are different and I don't think the 03 lower intake will bolt to the 96-98 heads. They are similar motors, but not exactly the same.
You need all the intercooler hoses and pump, the blower, intake, intercooler, all lines, heat exchanger, power steering bracket, alternator, pigtail and brackets, plastic air intake tubes, injectors, IAT2 sensor and harness if you want to run that one or just use your stock one, but the stock location isn't ideal. You need the timing cover, pulley bridge with all pulleys and idlers, hardware, etc.
i think those heads are different like the mark 8s those are B heads the car would need C heads for it to work.ive been looking into doing something similar and u can piece them together if u search for relitivly cheap.
hes gonna go go go baraaaappppppp THE BIG O!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
hahahaha thats funny, the heads are different like i said but if u already have a blower u can find heads cheaper then "real" 03 cobra heads...the aviator and the mach 1s have the same heads that u would need for the blower application good luck with your build.