[pff]

I had to replace an exhaust on a 2000 P1 (v reg) B5244s2 engine and it was a nightmare; bought two exhausts that did not fit despite being promised they were correct. eventually gav up and bought from a volvo dealer which was also a problem becuase the exhaust is two parts, a middle box and a back box that are pasted together with a slip joint at the rear wheel.
Initially they sent me just the front box for an eye watering amount of money and then after some detective work decided that the second rear silencer section was required for a similar amount (i am very grateful to them for covering this cost, the total would have been more than i paid for the car). The exhaust lasted exactly two years before every single joint failed due to rust. having a quick google the part numbers i believe were 31372159 & 31372156 if that helps.
the two that i bought initially looked very similar to the ebay linked picture but the problem with them is that were too short to clear the back of the car but too long to manouvre through the back wheel frame part where the joint should have been, i had to grind off the welded hangers to even have a chance of getting it to fit which isn't ideal.
I would suggest you have a good look under the car and have a good understanding of what is required, if you have to route it through the frame at the back wheel then there is just no way a pipe that reaches the back bumer will fit through, it will have to be in two parts that fit together.
In the end i bought my own 3/4" 304 parts and taught myself TIG, well worth it compared to what i had to pay to get a proper exhaust that actually fitted and lasted only two years.