As this question points out the routes from Sweden and Denmark to Newcastle has been discontinued. Driving the whole way from Stockholm (for example) to Scotland is some 26 hours and geography suggests that there may be a ferry option parts of the way.
What I have come up with this far is the Gothenburg-Kiel ferry (a bit off when coming from Stockholm) and the Amsterdam-Newcastle ferry. Are these the two best options for combining driving with ferrying or are there more alternatives? (Apart from the freighter options already listed in the referenced question.)