You would need some heavy duty springs I would think. But you wouldn’t want them so stout that when you unlocked it the entire top goes flying open in .05 seconds.

Give me a few and let see what I can come up with.

[url=Yonisun 1-5/8 inches Stainless Steel Heavy Duty Screw Eyes Lag Thread - 12 Pcs - Hanging Hooks - Eyebolt [ Hooks Eyes][Screw Eyes] - Small Eyelet Screws https://a.co/d/1sU3HZg]Eye hooks[/url]

Put an eye hook on underside of the top and another eye hook on the opposite long side of the locking mechanism. When you unlock it the springs should pull the top open.   That is how I would start and it would probably get modified from there.

Hollow legs to hide counter-weights and some eyelet screws could work and wouldn't be as violent as springs.

Some gas struts like for an SUV back glass/liftgate might work, but would have a reduced range of motion.

Fanciest way would be something like a power window mechanism.

Use car hood lift supports you would just need to find the right length