Rear seat removal from P80 wagons

[SonicAdventure]

Trying to remove the rear seat uppers. I know they are hard to remove, but even after removing the black clips, I’m getting no play on lifting the aluminum brackets up on either side. I’m assuming some kind of galvanic corrosion between the steel post and the aluminum is the culprit here.

Thinking I may need to get a small Jack in there and try jacking them up to break them loose but I don’t want to break the seat. I tried putting a block of wood on the floorboard and using an iron pipe as a lever while the seat was leaned forward but even that had no effect. Any other suggestions or ideas?