Martin -
According to this web site
http://www.rvusa.com/rv-guide/2012-t...t-deck-tr12457
the 2012 Sportdeck 16RD has a 55-amp converter, which is about the same as other TMs. The converter will be indoors (it is not waterproof), down near the floor (it is heavy), with a grill (probably brown) opening into a hallway or open space. The furnace has a similar grill, but you can tell the difference, since the converter has a door on the front and the furnace doesn't. Most likely it is under one of the dinette seats, behind your feet as you sit on the seat.
As for jacking, you can place the jack under the frame, just behind the wheel. But DO NOT place the jack under the axle.
Bill