Quick question, does the S5 have a chassis ground in between the negative terminal and the engine ground (that goes on the starter body) like the S4 does?

Apparently this one of the most important grounds (the driver's side strut tower ground, I think), but I don't remember finding it, or attaching it.

I looked for one but all I could find was those harness restraint peices (which aren't bolted down since it's a pain). My harness is fairly unrestricted (besides being pretty much stuck to the engine).

Maybe I just need to look harder...

 

Found it an cleaned it.

I was looking on the wrong harness...

It didn't seem corroded but it was pretty gunky all around it.