47-55.1 1947 Rocker Panels

[Dachshund]

OK....so I am planning to fix the rust bucket Swiss Cheese cab....too much sentimental value for my wife in it to replace the cab. My first question:
Which rocker panel is LH, and which is RH? Since the old ones are rusted to death, I can't tell which is which, and the stickers are no longer on them. I ASSUME the large holes in one end go toward the front....
THEN.....where do the front pillars weld onto them? Again - I ASSUME it is onto the flat spot just ahead of the rib. Any guidance would be greatly appreciated!