I'm out of town at the moment, but I might be able to try once I get back. It sounds like a fairly basic Plexi to me. I would try the MRSH M25 and see if one of the U47 captures get you close. This is a total shot in the dark, but I'd start with a Jumped Plexi, with the Treble Volume around 3-4, Normal volume around 1.5-2. See how U47-1 feels with the EQ knobs at noon and tweak from there. With Marshalls, I tend to tweak Presence first, Middle second, Treble third, and Bass last. Or just try the Jimmy Page Plexi settings from the preset I made for you and see if you like any U47 captures with it. Maybe add in a touch of M25 Room 2 and see where that takes you.
Thanks Justin, I gave it a go yesterday and attempted with the shoots you recommended. I did not get quite there but to be honest I am terrible with parameters so I would wait for you to have time - there is no rush at all!!
Cheers and well done again for making these amazing IRs