The D180 is D100 and D120 hardware in the same box, which means the pinouts are the same as a D100 and a D120. On top of that, the D100 has the same pinouts as the D10A, and the D120 has the same pinouts as the EMS-D10.
What this means is that you could buy an EFIS-D10A/D100 harness from us, a EMS-D10/D120 harness, wire them up, and it would work.
This will cause some redundant wires, but it won't harm the unit. The two most obvious redundancies are power and DSAB. The power and DSAB connections only need to be made at the EFIS connector (D-25). Power and DSAB connected to the EMS connector will be unused but won't hurt anything. You still need the serial port on the EMS connector as well as the serial port on the EFIS if you want to do any datalogging. You only need the EFIS serial port if all you do is software updates.
Basically, if you really would like to start wiring things for a D180 today, wire up everything as you would for an EFIS-D100 and an EMS-D120, but leave the power wires and DSAB wires off of the EMS connector.