Dear Riya,
there is no difference in the normalization, only you have to do the normalization with the total primary weight, instead of total particle number. This also applies if biasing was used during step 1.
So the normalization formula is:
Result_{normalized} = Result_{step2} \cdot \frac{Tot. weight_{recorded}}{Tot. weight_{step1}}
This assumes, that the recorded weights are correctly applies in the source for step 2.
Cheers,
David