Roland Perry gurgled happily, sounding much like they
were saying:

Even on stuff where space isn't absolutely critical, it can be
difficult. The battery on the Saab is nominally the common 069 fitment.
Nominally. You have to be VERY careful on brand, as many just plain
don't fit, because the OEM one is narrower than the standard. The one I
bought, I was lucky. It's a very tight squeeze, but just about fits,
with the exhaust touching the heatshield clamped to the side of the
battery.

That's only because the car has been designed on the assumption that a
special battery isn't a problem. if there were only a few different
sizes then they'd have to engineer round it.

Not quite - it's because the battery sat there all along, then some
pillock put a bloody great big turbo in the only possible place, which
put the exhaust... ummm... there... The exhaust routing's compromised by
the need to squeeze the battery in.

Why _should_ something so relatively unimportant arbitrarily be the
single most important bit of packaging?