Rubrignitz

Yeah, it's not too difficult to just remove that bolt every so often and replace the spacers. Just remember you have to loosen the mount bolt under the rear seat to swivel the mount to get the bolt all the way out and that CAN be a pita. But replacing that mount was also a major pita so wtf.

Not sure why your buddies is ok. Maybe he torqued it down more. Hell, I've seen two parts from the same aftermarket manufacturer with different clearances and such. Could be anything.

Riptide

I know my friend's 07 is totally untouched. He has never torqued that bolt down or installed spacers. It's an OEM mount, arm, bushings, and fastener(s). NO CLUNK.

And yet some cars clunk like a ****. If I had to take a guess I would say it's manufacturing variances. Either some parts fit better together due to machining tolerances or some are torqued down tighter than others.

Rubrignitz

Now to go chase down the squeek, squeek, squeek from my new energy suspension spring isolators. Not as annoying as a clunk but still annoying. I should have known polyurethane isolators were going to squeek!