Hmm. Well, the drawing on page 2 of that paper certainly doesn't look much like the shape of that thing in the MSL model -- you can see the RTG very easily in the latter, but NOT in the former. In particular, in the drawing there's no evidence of the flat rear cover plate which exists in the model and shields the RTG from view. (In fact, the silhouette of the combined RTG and radiator-fin assembly on one diagram of MSL as seen from the front led one earlier contributor to this site to enquire whether Batman was hitching a ride.) Is it still possible that JPL did a little fiddling with that model for the press conference to cover up the RTG, or is it just the result of a different viewing angle or a system redesign?