Miller Spectrum 875 THC Wiring

We have a Miller Spectrum 875 (NOT the auto-line version) we were planning on using with our soon-to-be-delivered CrossFire Pro and the torch height controller. I’ve read through the THC wiring instructions and wondered if others can confirm what I’ve found.

According to the Miller user manual, the rated open circuit voltage is 400V, which is greater than the 300V max listed in the THC manual.

Here’s my question - have I read this correctly? There is also an output voltage rating of 140V listed in the specs. Is this the value I use?

Assuming the 400V value is correct, can we still use the THC but just not turn the voltage too high? Or does anybody on this forum know if there is a divided voltage available on the machine somewhere?

Thanks in advance!