i second Noah's last comment.
could be a lot of wasted effort.
i work in PAL land myself,
and the last film i cut was at 24fps.
we simply made all our screeners as NTSC.
never had a problem.
if you decide to go ahead, you have two choices for turning the master file 24p into 50i / 25fps
1- using compressor, with frame controls set to better or best (can take a long time)
2- make a COPY of the file, and use Cinema Tools to "Conform" the clip prior to mpeg encoding in Compressor.
this is instantaneous, and you get a direct frame-for-frame correlation, as the clip simply plays a bit faster.
downside is: the clip now plays a bit faster.
4% faster, and audio is pitched up slightly.
nick