Hardtop Release - 380SL

I recently purchased a 1985 MB 380SL and I am having trouble removing the hard-top. The rear locking pin seems to be jammed.

I release the 4 pins, 2 in windshield header bar and 2 behind the doors. The levers for the rear release are placed according to the manual. The rear pin seems to release, but when the top is lifted the pin doesn't clear the trunk and appears to remain latched. There is movement and when the lever is reapplied, it pulls the rear pin and top back to a 'locked' position.

Thoughts?