730 Main bearing

DAB used the FM numbering system with some
changes. The rod bearing #'s in FM and the individual main bearing #'s in fm all started with a 2 , dab changed the 2 to a 7 ,so your 7430A is the same bearing as an fm 2430 rod brg,
and the 7431A individual main brg is the same as
an fm 2431 main brg that is used positions 1,3,5.
The aftermarket uses the same brg # for all
sizes ,but has the standard or undersize either
stamped or printed on the back of the brg . The
only exception to that was clevite about 30 years ago (only for a few years) used a color code on
the edge of the brg about midway around ,that idea was a flop. The other way to find what size the brg is would
be the measure the brg wall thickness , that dimension is given in the bearing catalogs.I have catalogs from several brands if you need the
info.

george