Fender extension drain holes?

[WissaMan]

One of my current projects, which started out as repairing some rust in the trunk of our 68 300 convertible, mission creeped into also replacing much of the sheet metal in the trunk extensions, both inner and outer sections. I have been wondering if I should add some kind of drain holes or channels to this area. I don't believe there were any drains from the factory, which is probably why they rust out so quickly in that area.

I do plan on rust proofing as best I can with a POR15-like coating, both inside and out, topped off with an undercoating on the outside. Actually, I'm going to be trying out the KBS products for this project. I've had good results with these kinds of coatings, but I know it's never good to have water just sitting somewhere and even the best coatings will fail eventually in that situation.

My biggest concern is that drain holes in that area may actually allow dirt and moisture to enter since they are behind the rear tires where that will get kicked up.

 

[CBODY67]

I believe there should be some drain holes in the vertical sheet metal on the outer trunk floor, at the sides, for the factory anti-corrosion "dip fluid" to drain out of, which are plugged with rubber/vinyl plugs, convertible or not.

IF there are any drain tubes from the conv top well, I suspect they would go into the rocker panel area for drainage rather than into the wheel well area? Factory sunroof cars usually have ONE drain per corner of the sunroof assy. One down each A-pillar and one down each C-pillar, with the rear ones going into the wheel well area, typically. Which is why I would suspect a similar rear drain for covertibles, but it might end up in the rocker panel area instead? Might need to find a body repair manual which covers convertible top items?

Just some thoughts,
CBODY67

 

[WissaMan]

I took a look at the rocker drains and I see they're more than just holes, they're actually long channels that are swept back, I assume the idea of that design is not only to keep water and debris from entering there, but also to create a low pressure zone to help suck air through them to dry them out. I could envision making similar channels at the bottom of the trunk extensions, but it's too late for the driver side, it's already welded in...