Most ppl fit the bung hole for the EGT probe just on the bend on the dump pipe about 100mm - 150mm post turbo.
Wait till you get a high flow cat and do things at the same time, You may want to ceramic coat the dump pipe or as some
have done is wrap in exhaust material. Its all about thermo dynamics and keeping the heat where it belongs inside the pipe
and not radiating out, and causing hot spots. . Thats why Ive fitted a turbo beanie keeps the heat inside the turbo and pipe
and also keeps my Aux battery very cool another plus to stop your aux battery exploding. food for thought.
Some battery places wont fix an aux battery your a 3lt TD patrol