Robin,
We can agree to disagree on that that bar is called, however, if you go to companies such as Art Morrison, Chris Alston and many other chassis shop's websites, they clearly call the diagnal bar either a "diagnal bar" "Z-bar/Z-link" not a Pan Hard Bar. Where they do call it a Pan Hard Bar, it is as I have described.
To add to that if you picked up books such as Suspension Engineering by Herb Adams, he explains the different rear locators such as a PHB, Watts link and Z-link (diagnal bar). I'm not sure why the company you purchased your suspension from calls it that, but they are calling it a PHB in error.
One of the differences with a diagnal bar and a PHB is what happens with the rear centering when the suspension is compressed. With a diagnal bar, if you compressed one tire with a sway bar attached the other would go up as well and both tires would stay centered. With a PHB, once the one side is compressed the other side compresses as well but, the bar changes its length based on how far it is compressed shifting the rear to one side slightly.
The problem with a diagnal bar is the bending force that comes in to play in hard cornering with a bump (road racing ect). As the passanger tire is compressed it want to push/pull the front link on the front driver side. Under the same cornering force, the PHB doesn't see the same bending force as its connecting points allow it to move the rear to one side or the other based on it's level with axle centerline.
As far as mounting the exhaust, you are probably right about it being dificult, I was not there to see the angles ect you were dealing with.
Please don't take what I am saying as an insult, I'm just trying to correct the term you are using based on the rear suspension research I have done.
