I have been experimenting with this for quite some time.

Tracy uses the old fashioned D sub min connectors that were
widely used in computers some years ago starting with IBM PC.
These connectors are very reliable and low cost but are tedious
to solder to say the least.

The screw down terminal block connectors are a lot easier to use and wiring
mistakes can be easily repaired. My AV8 eng monitor  uses them. Also they are
a lot easier to trouble shoot. They come in different pin spacings.
.1 inch, .15 inch and .2inch. I have tried all three
and the .15 seems to be the best compromise between ruggedness
and PC board space consumed.

I have been buying and building break out board to ease
the problem. A break out board converts the D Sub min to something
more user friendly. It is best to use them on the computer directly.

Here is my latest design using the .15 spacing
terminal blocks.

The other thing is; all D-sub min wires go through one ECx connector so it
is difficult to trace wires and repair.

My latest design groups color coated wires in four jacketed  harnesses.

They are PCM, Coils, Injectors and Engine Sensors.

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Here is a schematic of the PCM and a block diagram of the EC system.

Paul Lamar