Goofy question, but are you sure the front door speakers are 4 Ohm? I didn't pay much attention when I swapped mine, but I thought they were all 8 Ohm. In my 855 I have eight speakers, four in the front & four in the back. The rear channel speakers are wired together so the HU had two pair of wi...

One might think of the spacer as sacrificial material. $3.50 is a whole lot less the cost of replacing a worn out Spring seat and/or Plate. Look close you might find the old one. FCP one for example doesn't mention it: It gets missed by a lot of people, including professionals. If it has been servic...

I see lower torque in Alldata, 35 Nm and 60 degree angle

Note that new hardware is also specified.