I've replaced the Cat & O2 Sensors on My Disco 2 SE7. The Vehicle apparently doesn't like the new O2 Sensors. Lesson learned that I should've bought Bosch for them. When I was under the vehicle, I noticed the Cat is pretty darn close to the drive-shaft. I'm guessing within about 5mm. Is this a normal condition? I also ended up with a less concerning slight touch/rattle condition on the tail-pip to the frame.

Any advice on this would be helpful.
Thanks.