I checked the specs on that model. Since it does not have electric over hydraulic, that rules out two of the four options. Since it is a very lightweight TT, I'd set it up for "light electric". The test it at about 25mph to make sure it's adjusted correctly and stops the vehicle per the owner's manual.
2016 Ford F350 Turbo Diesel SRW 4x4
2017 Grand Design Reflection 297RSTS
2013 Ford F350 Turbo Diesel SRW 4x4 (Destroyed by fire - 8/29/16)
2014 Grand Design Reflection 337RLS (Destroyed by fire - 8/29/16)