Aftermarket ones will always raise the height as they go between the seat and the base.
You will also lose the ability to height adjust as the side seats trims will block the swivel when down.
You can buy aftermarket shortened bases to address some of these issues but you can't always use those if you need the space for your leisure electrics.
Additionally you'll need to lower your handbrake mounting.
See here for OE options
Howdy, long time lurker, joined in Nov22 with my new to me T6 Kombi. Driver seat has the OEM swivel base, never going to used and I just don't like lack of height adjustment. I found a few new/used OEM height adjustable bases online - 7E0 881 618 B (image below) - is it feasible to change the...
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