If you are handy with a screwdriver - that is a good start.
You will want to have the wiring diagram pages for you r year printed out and handy. they are on the site.
The DD comes with the sending units for the inputs and a pulse generator for the speed input (a VSS). When I do them I take out the dash pod and gain access to the wiring plug for the dash. ALMOST all the wires you need to connect to are there, just splice in and make you a harness about 24 - 30 inches long to run to where you want to mount their control unit. Just above the gas pedal on the hump works out nice. Then a ribbon cable they supply runs from the control unit up to the DD dash. Your original plug will go to nothing anymore. I do a little re-wiring there and keep the brake warning light and the check engine light if you are computer controlled.