I must have missed this. But, I don't believe Bleach is the way to go, like
some of the other cleaning products it's corrosive, 30 year old thread will
succumb to the ravages of Bleach just as the blue color in your jeans will.
Get to much of that stuff on your head liner and the sewn together cross
bars to the head liner holding it up will part and then there will be
trouble. It may be ok for the vinyl but the thread will dissolve if the
strength of the bleach is to much. And, to little will leave the yellow
stain from the padding glue.
Bill