The described pack-off assembly includes a tubular sleeve that is configured to selectively encompass a pack-off wireline seal and that is positionable through selective application of pressurized fluid to one or more actuation chambers that interact with a piston portion of the sleeve. Pressure may be applied to position the sleeve to encompass the seal to engage a wireline and enable pressure-control wireline operations. A different pressure may be applied to position the sleeve to expose the seal for servicing.