Quick question

[Richie200]

Will a 996 3.6l cat back exhaust system fit a 3.4l C2?
Especially mounting points, tip location...

[jkh112]

Assuming the 3.6 boxes are not from a C4S (or turbo, GT3, GT3) then yes. The exhaust finishers will be larger on the 3.6 box but they should still fit on a 3.4, or if not then the tips can be swapped. The boxes on a c4S are the same but the exit pipes leading to the finishers are longer and so will need to be swapped.
All this also excludes PSE boxes which have a valve to alter the gas flow.