1993 240 Wagon
197k

I'm replacing a bad cat with a new Bosal unit I ordered from FCP:

https://www.fcpeuro.com/products/volvo-catalytic-converter-244-245-240-099-6431

But I'm not sure how to seal the connection between the two.

Here is a picture of the header:



And here is the cat connection:



Bosal included both a thin gasket as well as this cool looking one:


I think I'm suppose to use this metal-mesh insert between the two since the surfaces are different connections. I can easily slide the sleeve of the metal mesh into the header, but it will NOT go into the cat.

What is the right way to get the seal air tight? I don't want to buy a new header if I can avoid it.

Thanks.