2023 Tacho Rules / 4x4

Cant seem to find anything recent on this, with the recent changes to B+E and the weight of most 2022/23 pickups going over the 2040kg limit. Just looking for some clarification as the laws are clear as mud and the DVLA don’t want to say very much.

My understanding is this, please correct me if I am incorrect as it’s a minefield for hire and reward:

Dual purpose vehicles under 2040kg unladen AND SUV’s are exempt from O license requirements and can tow 3.5t if rated to do so & total train limit within towing spec and under 7.5t (3.5t+3.5t)

If towing for hire and reward with above, a tacho would require to be fitted to both.

My next question if the 4x4 is not towing, if a tacho is fitted to the 4x4 can I still use for personal use? Can a non tacho card hold drive it? As it would be used for personal/business use. How does this all work as never had to use a tacho before.

Personally, the whole thing seems a bit of a sham! Especially when trying to run legal.

With 2023 ford rangers being well over 2040kg unladen am I correct in saying these would need a O licence and tacho to run legally?

Any insight or advice is more than appreciated