Dad and son have have an 87 E30 that had a small engine fire. Principle damage is the wiring to the injectors. We have a donor car (85 E30). Is it possible to replace only the damaged part of the harness or will we need to replace it as a total unit? I'm reluctant to start removing the shrink wrap from the harnesses looking for a connector. We have the Bentley manual and we recently moved the manual transmission from the donor car to the 87. We did this with Jack stands, no lifts and no prior experience. I just want to calibrate you on our level of commitment not our skill set. A step by step procedure would be much appreciated.