The "Facelift" version you are talking about is the one that came in 96 in US?
Now The 93 and 94 models all arround is very identical, but the 93 had an extra coolant temp sensor, the 95 in Europe is the same as the 96 and 97 minus the airbag on the passenger side, this is the Pre-OBD-2 version, the 95 EU is very identical to the US version, but then again US had airbags since 93 and the 95 version had a different kind of version of how you turned on the headlights, turnlight etc. on the steering collum, this was moslty due to the Airbag and I think the US is the same for all years (can't confirm) but the differences was that the 93 and 94 EU had a few relays triggering the different things, while the 95 had the relays integrated.
In 96 the OBD-2 system was introduced to the cars in the US, MX-6/626/Probe, but not many with a manual transmission, mostly automatic, I got myself a complete harness from a OBD-2 MX-6 M-Edition with Manual transmission. A local friend got one from a 97 626. Since I never completed the swap and got it working correctly, I don't know what's different, but I know the MX-6 has the steering for the power mirrors on the doors and might cause a problem for me. And the plug connecting the rear harness to the front harness is what's different between US and EU, and the US had the clutch safety switch in order to start etc. I never managed to get the starter to work with the harness, only if forcing it, but I had to get the fuel pump to run which is connected to the rear harness. I actually got it working, but it ran constantly when the ignition was on..
The immobilizer system was some crap as said, hardwired into the ECU and a keychip with some kind of decoded below the steering wheel, so when I replaced the harness from a 93 I didn't need that anymore, but I had to rewire the control arms for the headlights etc. in order to use the one from 95, had to put in a few relays in order to make it work, luckily my local friend had most of this covered, so a multimeter and patience was all needed
Now for the Tüv is where we get most of the papers for lowering springs etc. and they are easy compared to the stupid shit we have to deal with here. But does the 93 and 94 have any immobilizer in Germany? If not then why would it be so hard to get it approved if you replace the harness? :S I understand the insurance will be a bit more, but if you get the MAF mod working I would say it is worth it.
I will get the US harness to work on my 626, even tough it is from a MX-6. That is why I am looking for the wiring schematic for the European version
Might just have gotten a Megasquirt system, but I couldn't have gotten it to be OBD-2 then, as the MAF requires it (You use a Millenia ECU, OBD-2) but I got a OBD-1 to OBD-2 harness I made, but never got the MAF to work correctly.