HT furnace, adding a second thermocouple port/hole

[HSC ///]

I'm having a furnace built here in France.
I'm thinking I'd like to have a secondary hole available to measure temp with an external Omega reader
Where would be the best place to add an additional hole and why there?

The builder will put his T/C in the middle back for the furnace.

FWIW, A Thermolyne furnace I had back in the USA had a secondary hole in the back to add an additional thermocouple.

thanks

screenshot from the builder's FB

 

[DanF]

Watching this.
I put a second in my Paragon centered in front door as the factory TC was in the back, slightly high. When I performed hardness tests there was a difference from tip to tang in hardness so I wanted to see if it was cooler nearer the door and having a second TC helped verify the first.

 

[Robert Erickson]

I have an Evenheat KF22.5 and I put a second K type TC in the door close to the floor of the kiln. In doing a bunch of coupons this TC was more accurate than the factory one in the ceiling (with my setup at least)