frozen handbrake

[tsheard]

My '69 avanti came with a frozen handbrake. previous owner tells me he never used it. The manual says to remove the cotter pin. I THINK this is the pin just behind the bracket under the dashboard behind the plastic handle; I can see one end of a pin, but I can't see the head of the cotter pin or any way to remove it. suggestions would be greatly appreciated.

I attached a photo of the brake if that would help clarify the situation.

thanks!

tim sheard, brooklyn