In theory I should be able to take the EuroCarParts one back for refund if I don't used it.
So presently just hoping the new cat shows up in a timely manner as implied (should be tomorrow). I have new studs and exhaust/manifold nuts on the way too (prob later in week, from Spalding Fastners). So probably Saturday morning I will be reassembling, hoping it is sound, and fingers-crossed get the MOT passed. 🤞