Nathaniel Merrill wrote:

Anyway I intend to seal my new one well with oxy sensor safe rtv
silicone.!

hello
Please do not seal O2  sensor

O2 sensor is not made to be seal
O2 sensor is vented to atmosphere by the small gap  near the nut
If you look carefully  near the nut you will notice  the cap of the O2
is just crimp  at four or six places
I  should explain more deeply but my vocabulary   in english   is not to
good

Denis
westie 85