So I FINALLY realized the dream... was practically
given an S8 exhaust, from the frontmost clamps to the tips (so pretty much the entire horizontal section); it fits with very little alteration (!) and
that small change is accomplished with a wrench (the rearmost mufflers' brackets are 2-3cm off, but by reversing the bracket - two bolts - they hang just right). The "stock" S8 system had two cylindrical resonators each about 16" long where most 4.2 petrol cars have their "suitcase" silencer. It was not much louder so I removed them both. I do regret to report that my hair is full of very sharp stainless swarf, but at least my eye protection worked.
Videos with one middle silencer removed and then both removed,
and the whole album with measurements of S8 exhaust..
More action videos to come...