I've had very satisfactory results from the 303 Aerospace kit, it's an Amercian product, not likely to be too widely available in UK apart from specialists
It's a 2-stage process - first a deep clean, and then a retreatment of some protective spray.
Someones got there already with Renovo: excellent product tried & tested many times in the UK. They even do a product to change the colour of a mohair roof to a different colour & it works very well IMO, naturally going darker NOT lighter! Oh & if you ever do it, dont be tempted for a second coat for better results: you will end up with a crsipy duck finish! Been there! :-0
Another product I can highly recommend is the 303 range (fabric guard and fabric cleaner). These guys actually make a lot of the fabrics on these cars so you know the product will do it's job - and do it well. I use the Aerospace Protectant on all my black plastics and as a tire dressing - brilliant stuff!
I purchased an Audi TT from dealer, car was mint hood was dirty, garage washed it with shampoo and jet washed it off, had three goes, hood looked like new, to waterproof I used FABSIL, absolutely brilliant, used for reproofing tents and recommended in Audi TT forum.
Spray can cost £4.50, one can did TT roof. Method is spay small area of roof at a time and dab in with lint free cloth. It is the cheapest water proofer and more than equal to all other more expensive brands, if it is good enough for tents it`s good enough for car soft tops.
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