Thanks for the comments guys.
Car is a July 65 Dearborn, and yes, did/has the vent hoses.
I've had this car since 95 when I shipped it to NZ from LA (Rockford DSO). Was in poor shape/been raced and I "restored" it as best I could as a kid in my 20's before the internet came along and in a small, remote country (parts).
Been in a few minor accidents along the way (none my fault, mostly people staring and forgetting how to drive), driven in the NZ snow and shipped home to Australia in 2000, so it's seen it's share of challenges over 25 years....
The current state of the car is result of visible rust patches coming out at the location mentioned at rear of sill. We chased it up through the quarters and found minuscule traces under the paint. Already had some minor rust in the rear window surround.
Seemed as good a time as any to replace sheetmetal with traces of rust and previous damage, plus some historical poor repairs from pre-95.
You are correct in that it's probably seen it's last snow and certainly won't be spending any more time on the ocean
Also, as you can see, every surface has now been epoxy coated, even up under the quarters where I found miles of bare steel.
Maybe this won't become an issue going forward, but now is the time to ask and haven't seen it addressed before.
Stay tuned for the next silly question.....
Cheers
Wazza