On my ford motorhome I have relocated the OBD port to the centre of the dash in a lockable dash, and the lived up a dummy port in case people try their luck... I had the Hykee lock fitted when it first come out (before the additional surrounds were available) and have since purchased the surround, however the hykee lock is so firmly in, id damage the motor trying to remove it to add the ring, so ive got a surround i cant use. Have you thought about rotating your seats and locking them facing the other way, or chaining the steering wheel to something solid? I clutchclaw also works great, and theres some new pedal boxes floating around now also which remove access to the pedals entirely...
Either way, if someone wants the motor enough, they will still take it, we are after all just buying time. Alarms and trackers are great but the are all bypassable.... wheel clamps are good too... but nothing stops someone picking it up and taking it, regardless of how much you spend on security. I’m just looking forward to getting out in the motorhome and relaxing....