I get 4 of the same codes as yourself P1146 P1166 P1147 P1167,
these come up fairly frequently, sometimes not all of them at once.
I also have berks hfcs, a scorpion, and an Uprev.
From what I have read it is safe to run, but spacers may help?
I've not got my spacers fitted my tech had some issues fitting them (if you can believe that!) so I'm currently trying to get booked in with my usual guy to see if he can sort it.
I am hopeful that if I can get the spacers on, this will put it to bed. If you do pick some spacers up and it resolves your codes (as expected) I'd be very grateful if you post up on here, given we have the same set up.
On the positive side I have no evidence to suggest it's causing issues beyond the irritating EML and the O2 sensors are getting lightly toasted due to the extra heat.