If you haven't already, bookmark Brookhouse as a one stop shop for virtually any parts you need. Omega clips etc. Exhaust clamps/fitting kit, speedo cable etc. It's common to rotate the silencer box you show, to get everything to clear but that may be too far, especially if the final supports have been pulled up too far. Loosen all of the clamps and twist them around a bit. The whole system should "hang" and not be tight anywhere. Generic rubber rings can be too small and pull everything out of position.
https://www.classicvolvoparts.co.uk/