Ricky,

I to will have to do my wiring harness in future. With 171k miles on my 500E the wiring is brittle (Seattle weather car) but everything works with the exception of the ASR light staying on with the ASR system funtioning correctly 100% of the time.

My plan is to just order the various connectors and reverse engineer my own. After all, we are only talking about wiring and $500 for wire is a bit much in my opinion.