I am taking apart the windshield for my '39 Chevy truck and I got the center division bar and the connector bracket for the crankout assembly off. I got all of the screws on one half of the windshield off, and tried to separate the halves. The top of the frame is sliding apart, but the bottom is frozen shut. Is this just a rust problem? Is the best solution just soaking it with penetrating oil?

1939 Chevy 1 1/2 ton dually rear wheel pickup
1940 Chevy 1 1/2 ton single rear wheel pickup
1946 Chevy 2 ton cab and chassis
1977 Chevy 3/4 ton camper special 4x4
Obsessed 16yr old Chevy truck nut