Received mine from e-acca yesterday and couldn't wait to do the install so I finished it off before the sun went down. I'm not as smart as the rest of you guys so I bought a pre-made harness from Zero815 and I'll give a brief review here. The guy is fantastic. He's extremely helpful, the harness was made with beautiful quality and shipped out lightning quick. He offers customization and helps to clarify the coding.
During the install I borked an adaptation when I accidentally set the Leuchte17 Lichtfunktion A17 to "Blinken rechts Hellphase" when it was supposed to be "Blinken links Hellphase". A quick email to Zero and in less than 5 minutes he had responded with the solution.
10/10 service. I would never hesitate to direct someone his way for a harness. I'm sure the other sellers for these are good too but for the service and ease of install I'll go with Zero every time.