IMO easiest to retain the 185 engine loom and just change the few pins required on the ECU. Much less effort than trying to mate a 205 engine loom to a 185 body loom as there are some incompatabilities.
The following has a list of the pinouts of various ECU's.
https://dl.dropboxusercontent.com/u/831 ... iagram.pngCheck the part number of your existing ECU against the list and you can then compare pinouts against the rev 3. AFAIK the later 185 has very little difference. The main differences with earlier 185 from memory is the dizzy gignals (G1,G2,NE) are in a different place and idle solenoid is slightly different.
The main difference is the PIM signal (turbo pressure) on a 205 is in the place of the AFM signal (now redundant) on the 185. You will also need to swap the 185 'turbo pressure' sensor for a 205 'map sensor' as the scaling is different. (some later 185 may be the same, check part numbers)
If ditching the AFM you will need a separate air intake temperature sensor wired into the THA wire from the AFM.
You will also need to add a manifold air temperature sensor and wire to the THAM input on the ECU. You may be able to use the now redundant VS wire from the AFM for this function to save running a new wire along the loom.
I presume you have the usual .pdf downloads for the 185 & 205 including wiring diagrams so you can compare. If not, I'll dig out the links.
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