Radiators, New smaller one in Stage 2 kit?

[RoadRacer]

..that came with the Stage 1 kit and the ones that now come with the Stage 2 kit

you said Stage 1/2 a few times and I think you meant gen1/2.. but as you suspected the difference in radiator is due to the 33 or deluxe grill options.

the rounded one is the 33 grill version, I have that and still easily mounted inside a 32 grill, fwiw.