Isn't that what they call lawyers in OZ. (That's a nickname for Australia, or do you need documentation on that).
Most REAL car enthusiast simply accept the fact that we must make up a lot of car modifications to improve our rides, without needing significant evidence of the shortcomings of the car, or evidence of the improvements rendered by our cutting, drilling and welding of new attachments.
I used to race an early Austin Healey 100/6 and when I started racing it, it had numerous faults on the track. Body roll and body flex were just the beginning. Lock to lock on the steering was considerable, so I shortened the pitman and idler arms. Steering response to turns on the wheel became much faster, but the strength needed to turn the wheel also increased a bunch. I consider that the Healey required the same strength to steer as a US Army 2 1/2 ton truck (deuce and a half) being raced on Laguna Seca. I had the good fortune to race such a truck on Laguna Seca when I was in basic military training at Fort Ord (near Monterey) in 1964.
I subsequently sold the Austin Healey to another racer. After his first run, He commented, "Hey, this thing corners like a TRUCK". My point is made. How does one document that. We didn't have YouTube and Video Tapes in 1964. I do submit however that all my mods to the Healey were "improvements" to the vehicle.
I also know that the e12 has one characteristic flaw in body design and construct. If you have one that emits an intermitten snap or creak in the cabin, you simply have to pull the headliner back from the B pillar and look for a crack in the sheet metal starting where the B pillar welds into the roof on the inside of the car. When the body rolls, this crack has a deep snaplike creak during hard cornering. If one has the tower braces in the car, that crack likely does not occur.
Unibody construction inherently flexes based on how hard a car is driven. It's likely that BMW 5 series cars are driven harder than most average early unibody constructions. A lot of unibody construction over the years has been spot welded rather than seam welded. Spot welding allows better response to body roll than seam welds.
All e12 bodies are full seam welded, which turns out to have been a less durable way to construct unibody.
Therefore, anything you do to counter the flexing of the e12 body will result in less work hardening of the metal and cracking of the sheet metal ADJACENT to full seam welds, like around the base of the rear shock towers.
There, now you have documentation. If you print this out and file it, it will be considered as a document explaining strut bracing. My Documentation.
Next thing you know, you'll be querying us for documentation on whether the the rear differential mount really does develop fatigue cracks over time under hard repeated acceleration. I submit that the repair kit sold by BMW is simply proof enough.
