Right, just cleaned the car to get it prepped before polishing and decided to bite the bullet andtry and get this sanding done...
So as advised I soaked the paper overnight in a shampoo solution, and then rubbed gently over the surface, keeping it lubed with QD. The paint/ clear coat came back nicely so its flush with the paint, but when I wiped away the liquid I was left with some HORRIBLE looking sanding marks. Initially I was thinking "nice one Tom, this looks worse than it did before, worse even than the scratch I was trying to cover up!" but after going over the area a few times with some Menzerna IP have to say I am extremely impressed with the results, the entire scratch is almost invisible unless you look hard for it and the scratches around the repair are almost gone, going to finish off with some FF soon.
Anyway, cheers for the help - definitely a very usefull technique!