Exhaust question

Hope you guys can help.
Just bought a Tanabe muffler with a 60mm inlet.
I definately want to change the center pipe, cause it’s rusting and to match the inlet diameter of the muffer.
So question is:
1/ Do I also have to change the cat? I’m not sure but I think there’s
2 cat’s on an S14. 1 after the manifold and another one on the
center pipe itself.
2/ where can I get custom mandrel bent piping done and how much?
Preferrably somewhere close to Scarborough.

Thanks.