I used impregnated interior trim wipes (the packets that look a bit like baby wipes!) on my Aero 8 that also had very grubby interior of mohair roof. Worked an absolute treat and very quick. Dirt just stuck to the impregnated cloth.
Good luck - I was really pleased and rather amazed that I could clean the roof inside after trying normal fluids which just seemed to make it worse.
That sounds promising! Any more info on these wipes?
