Back to the Future question

ORIGINAL: COZ

After watching part 3 last night, I've got a couple questions...
I don't see how Doc's headstone could say "his beloved Clara".  He wouldn't have been at the ravine in order to save her.  Doc was only down by the ravine in 1885 take 3 (when Marty came back to get him) to check out the tracks and lack of bridge.  Therefore, she would have gone in and they'd never have met in Doc's original take on 1885.

When Marty does not go back to Doc, Doc picks Clara up at the train station as originally planned.  Remember when the mayor comes by and asks Doc if he still is going to pick her up?  If Marty didn't interrupt, Doc would have done so and it would have been love at first site at the train station, without her having to take a coach by herself and falling down the ravine.

Also, at the festival, Buford comes looking to kill the Doc.  However, it's Marty who saves him with the pie tin.  Without Marty there the first time around, shouldn't Doc have been shot that night and not the 7th?

Yes?  No?

Buford says that the last time he shot someone with the pistol he was using that it took him "two whole days to die" and estimated that Doc would die "suppertime Monday," which was the 7th.

Thanks phoojoe.  Those explanations both make sense and ring a bell for me now.