Body putty ?

[oldguy64malibu]

During the process of replacing the windshield in my 64 Chevelle convertible I removed the molding that goes across the top of the windshield frame. It is the piece that the convertible top seals against. Underneath the molding was a putty like substance that keeps rain from getting under the molding. I have tried to find this on the napa web site with no luck. Anybody know what this stuff is and is it still used or should I just use a silicone sealant ? Thanks for your help.