I am still waiting for the delivery, so I assume model x is just like other cars will need to install a separate trailer brake to tow a 3000lb+ trailer/camper that has a electric brake. For guys already received your x and plan to tow a "brake equipped" camper such as a airstream trailer that Elon showed in the introduction video, could you confirm is this car already has a trailer brake(included in tow package?) or we need to install one? If it needs to install separately, can Uhaul do it or preferably ask service center to do it(I assume SC charge higher cost)? Where is the best location to mount it on without making the interor ugly ? Thanks!