In terms of Electrics, Power windows will cost you about $400 from wreckers, 4 x (Motors, and pully assembly only). These are very easy to fit, and would take about 1 Hour for Each door. (The B@#stard thing is removing 3 Rivets that hold the assy in.
These from ford are are about $220 each.
Note: You will still need the switchgear, and to run cabling into the doors etc. - I Have Replaced 1 Winder in my EF, and have added electric windows to a VN and VR. I also added VR Berlina Interior to the same VN, the interior cost about $800 from memory, and included seats, door trims (with switches), and centre console. (I know this is Commodore pricing, but it is enuf to give you some idea of the costs).
The Instrument Cluster is about $150 for the Batt/Oil/Tacho Version from wreckers, but I think you need to be careful what model you pull these from, (IE EA didnt come with smart lock, so as they dont have the Smart lock LED. Also you will need an Oil Pressure sensor to do this)
There are other little things that you can add as well, Interior Lamp with Reading lights, about $40 from a wrecker - Just bolt straight in. Courtesy lamps in the footwells - (All you need for these is a bulb holder, very cheap and easy to add, bout $10 for the pair), Interior Light Delay Circuit, (Jaycar Electronics stock a DIY Kit, $8.00 Has the same fade function as the EF Fairmonts, I.E. Stays on for about 10 seconds, then Slowly fades out).
Finally, you may want to talk to exodius, he is currently installing EL Fairlane ghia interior, into an Ex EF Chaser. Looks very sweet !!
This is just to give you some idea's