I agree with John. Unless you have a really good, fine tip, adjustable heat soldering iron setup and the confidence to perform micro-soldering, you should not attempt it. The opportunity for failure is very high.
My shoebox did not come with an ECU, either.
The directions have you solder the breakout harness wire directly onto the ECU circuit board.
But once installed, what a great troubleshooting tool!
My ECU was working perfectly when I installed the shoebox and I was able to confirm that by performing the system checkout and having all the LEDs light up when they were supposed to and all of the sensor voltages were in the normal range. And the harness is long enough so you can have the shoebox on the dash while you're driving and see what's happening in real time.
Mike M

Sent from my iPad

> On Jul 12, 2015, at 13:41, Neil N <musomuso@GMAIL.COM> wrote:
> 
> Too much coffee. I meant:
> 
> Do the Shoe Box instructions say to solder interface connector to
> ECU wires or to internal portion of ECU pins?
> 
> 
> 
> 
> --
> Neil n
> 
> Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>
> 
> 1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy>
> 
> 1981 Westfalia "Jaco" Images, technical <http://tubaneil.googlepages.com/>
> 
> Vanagon-Bus VAG Gas Engine Swap Group <http://tinyurl.com/khalbay>