Hi David
I have had a squeak on my left hand side of my backside on my 09 Roadster for three years now, and have taken advice of spraying every product mentioned, but I still have a squeak on my A**e end, it's doing my Morgan head in!!!
My +8 squeaked originally, there were three sources, one was rear springs needing greasing as others have said. The other two were cured by regularly putting Acf50 along the rubber bead between the rear wings and running boards and the body, I did this to protect them, but found it cured a squeak, the other was were the doors meet the body and were rubbing which varied depending on heat and body expansion I suspect, easily cured bu buying small D shape seal from a Morgan dealer and also stops water ingress. Hope this may help you track it down.
