Adaptive Damping - 2002.5 S Type 4,2 V8

Looking for any information on how to test Adaptive Damping.
I am experiencing a light/ floating feeling over 80kph even after professional wheel alignment. It has been suggested that my shocks may be the problem.
I have a high mileage vehicle and have no idea if the shocks have ever been replaced.
When I try pushing the car down (engine off) I get very little movement but driving over bumps there is distinct movement.
Wondering if should remove the shock and spring to see how the strut operates i.e. too firm or too hard? Being “Adaptive” will this make any difference?
Also as money is tight and standard shocks are a little cheaper can I just fit a non-adaptive type?
Any help please. Dave

@Dick_Maury… any clue? I have none!