Only just come across this thread, so I'll just add my reflections...
My first two Stones concerts. The two Wembley gigs were over 30 years ago, so my memory is hardly pinpoint accurate, but I certainly recall the pouring rain, although I think it had stopped by the time they hit the stage in the evening. My mate and I were down on the pitch on the Friday, up in the stands the following day, watching the people on the pitch getting soaked like we had the day before.
Strettonbull's account of Keith kicking Ronnie is certainly the way I saw it, although I only just caught it, my mate noticed it a bit more. Someone sure messed up the intro at that point.
Can't really remember the support acts, although I was there all day! I saw Black Uhuru loads of times over the years (mainly at festivals), but that was probably the first time I saw them, if they were the support.
...and it's interesting to read about the transport problems, that might partially explain why we decided to crash in the car park overnight, for an uncomfortable night's 'sleep', rather than going home and returning on Saturday. More likely that we were both still living with our parents (aged 19), and just fancied staying up all night. I'm pretty sure I had to take the day off work for the first gig...they didn't play Sunday because Wembley didn't hold concerts on a Sunday then, can anyone else verify that?