Minimum configuration for running multiple TB Desktop instances

I am using Selenium WebDriver to run multiple TB desktop instances and would like to understand the minimum necessary configuration so I can run tests for such functionality in my application. The tests just need to prove multiple instances can be run on one desktop simultaneously and I do not need a user profile for any of them. I am aware of the potential privacy/anonymity implications of using parts of the TBB rather than the whole and am happy to accept these for testing purposes.

I know I can use multiple copies of the TBB and set the following prefs to available ports so they don’t conflict with other running TB instances:

This works fine, however, I notice there are prefs for setting a custom location for the torrc config file, tor data dir and the tor binary itself:

Is it possible then to use these and the above port prefs (and any others necessary) to configure multiple browsers (copies of the binary) to use their own torrc and tor binary without the need to make copies of the entire TBB?

If this question is better directed at your dev community I’d be grateful for a referral to an appropriate person. Many thanks.

My setup:
Linux Mint Debian Edition 6 Faye (based on Debian Bookworm)
TB 13.0.6
Standard security level