The DNO will give you a maximum length for tails. (usually 3m). You described the best way earlier which is to run them into a fused iso and then run off SWA it singles if protected correctly. Neither need RCD protection so won’t be a problem.
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc