Not really any special skills..."puzzle solving" maybe? A multimeter, wire strippers, a decent crimper and a soldering iron. The only bits that need to be soldered are the terminals for the 14 pin connector and for the reverse light switch. The multimeter is really only used as a continuity tester to help verify all of the connections. There are no resistors, capacitors or anything like that in there, just simple wires connecting stuff to other stuff. Just be sure to use the proper wire gauges for each run.
If you use the factory electrical schematic, it even gives you all the wire colors and proper gauge to use:
http://www.pelicanparts.com/911/911_Parts/Electrical/911_electrical_78SC_USA.pdf