CONVERSION

REQUIRED	

1)	engine
2)	5.0 main body wiring harness
3)	vacuum hoses and bulbs
4)	computer
5)	5.0 transmission (5.0 AOD, or a C4)
6)	trim the hole for the shifter or it will hit the floor pan
7)	switch the pedal assembly to a clutch
8)	reroute the speedometer cable
9)	5.0 driveshaft
10)	cross-member with two humps for dual exhaust-----> $ 67.99/each (mustangparts.com)
11)	8.8" rearend
12)	new fuel pump
13)	complete length of fuel lines from 5.0 OR switch location
14)	extend the alternator wires
15)	5.0 clutch and throttle cables
16)	5.0 vacuum distribution tree 
17)	4cyl power steering hose will work with the 5.0, just remove the switch from it and plug the hole with a pipe plug. The 5.0's come with an extra loop of solid power steering line for cooling so you probably want to use it. 

optional

1)	larger gas pedal
2)	new tachometer that will go up to 7000rpm, not just 6000
3)	new sway bar, more heavy duty for the 5.0
4)	The front brakes on a 87 or newer 5.0 are 11" while the 4cyl brakes are 10" so you might want to use the 5.0 brakes. To do this you need the spindles, rotors and struts off the 5.0 but the control arms are the same for both. 
5)	Also the 5.0 master cylinder will have to be used with the bigger brakes but either power booster will work. (all though the 5.0 booster will give the engine more clearance) 
6)	The speedometer will work fine as long as you use the right plastic gear at the trans for your rear-end. 
7)	The 4cyl springs actually do a good job of lowering the front of the car and are better than cutting 5.0 springs, but for the best ride go get some proper 5.0 lowering springs.
8)	*coil and starter switch are the same for both