DanTheMainsMAn said:do you know anywhere where you can get single phase cable 3 core but right colours
I have not seen any, afaik it is normal practice to sleeve the 3 phase colour wires at both ends with the correct colour sheeth.
The earth wires in the plastic CU all should have earth sleeve.
I am beginning to think it may be of sound advice to say get a qualified member of a competent person scheme to come in and do a PIR on your install for you.