One thing to remember regarding engine swaps is that in some USA
locations (e.g. NM, where I live) the swapped-in engine must be the
same year or newer than the vehicle, according to the emmissions
police.  This mostly eliminates Ford V6 from discussion in these
places.  Also, this situation, even if not the case where you live,
makes it difficult if you want to move here or if you want to someday
sell vehicle to someone living here.

Next, I'm not too familiar with waterboxers but know my air cooled
engine is constructed of magnesium and aluminum (with of course iron
and steel parts, too) and it seems something like a Ford V6 has to be
significantly heavier.  Wouldn't an installation like that make for
pretty light steering?  Can anyone post weight of waterboxer engine?