I am dechroming car for paint, its a 64 Vista. After removing trim around vista windows, the sealant is fluid almost like molasses. Lucky no rust was present. Cleaning out old sealant with acetone and wanted to know what type of sealant should I use to re-seal?

 

The factory used a setting compound for the windows. While that prevented leaks to the interior, it still left the window channels exposed to pooling water, which caused the channels to rust.

You are very fortunate there is no rust in the channels. The sealant is a clever solution and obviously did its job. Why remove it?

 

The sealant failed. Water was slightly leaking inside the car, hence new headliner. So I had to investigate. The sealant being a liquid after almost 60 years was not normal. It was in 90 degree direct sunlight, but even then, a liquid black goopy rubber? I scooped it out easy with a spoon. Then sprayed it down with acetone and cleaned it off easy. No sealant should be like that after 60 years. I think i will use a urethane adhesive / sealant to fix it all up. I see some autobody shops have lots of it on hand. I was just pleased there was no rust.