Ok I divided up the posts I had into two groups, not bad and real bad!
Tried the peroxide and uv using both sun and lamp and other than them looking cleaner it did not reduce the yellowing.
As Nino said it is not really worth the effort although separating them and using the brightest ones has worked out as they actually look ok on my 1973 Big Shot as I have cleaned the playfield up and it looks great but I am not going to paint the white under the plastics. If I am not happy at the end I can replace them then!
Cheers: Brettski... :)
