On my '51, I just noticed a couple of water tracks, inside the cabin, at the headliner J rail, drivers side. I don't remember what the factory did to seal that joint, where the roof and sides come together. But I'm going to have to remember to run some sealant down the full drip rail before I do final paint. Maybe I sanded too much paint out of there when I stripped it? As far as I can tell, the roof panel sits on top of the side panel rail that has the drip rail. Might have been better if they had made the roof panel with the drip rail lip that attached to the side panels. Ah, but what do I know.......
I've used a common DAP caulk known by the model name "Alex". It is siliconized but also easily paintable, indoor/outdoor and they claim a 40 year life. No idea what was used at the factory, but you don't want water being harbored in that crack.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
On the belt line of my 54 if I remember correctly I used 3m brushable seem sealer was done in1988 still on there although it is not on the top like yours in SoCal but in snow cal Ontario .I believe you can get the same stuff in a tube for easier apply .I used masking tape to tape off the area were I did not want it and used the rest for sealing were I welded patches on the underside .
