Hello Stef, I can understand your concerns about the hydraulic system In your Ford Gt, however I would advise that you keep the rear wing in the deployed mode to prevent body damage, when your rear wing hydraulic pressure bleeds off after sitting for long periods of time the rear wing natural rest position is in (air brake mode). That's when the front of the wing faces down. For this reason Ford has asked Ford GT owners to keep the rear wing deployed when sitting for longer then 72hours. Here is the service message issued by FMC.
48515 - 2017-2020 Ford GT – Paint Damage From Aero Wing During Vehicle Storage
Some 2017-2020 Ford GT vehicles may experience the front edge of the aero wing l owering when in the retracted position for longer than 72 hours without engine o peration. This condition may result in paint damage if the aero wing contacts th e inner quarter panel. To prevent this from occurring, the aero wing should be p laced in the deployed position prior to storage by activating track mode and the n returning to normal mode. For information regarding drive mode activation, ref erence the driving aids section of the vehicles Owner’s Manual. Engineering is i nvestigating the concern, monitor OASIS for updates.