Rockerbox/water drainage/ Rust ?

[pound41]

I am in the process of putting floor pans rockerboxes the whole 9 yards in my 70 blazer. Unfortunately I am doing it with no available garage space. I have everything almost ready weld back in. Anyway I have noticed when it rains. The water draining off the cowl/ fenders drains down and lands in the rockerbox area where the floor support inner rocker all tie together, It pools in the indentation in the rockerbox where the cab supports sits. Anyway from there the moisture begins to wick towards the inner part of the rockerbox headed towards the rear. Also it begins to travel down the rocker area. Reason I am asking is this normal? Because the water travels where it is rusted. This blazer came from western Tenn where it shouldn't seen a lot of snow and salt. In most of the blazers I have seen and owned when the boxes were gone.. they were totally gone. These are not. just on the inner seams. Anyway should I drill some holes in the boxes. Any ideas or experience.