Both blocks are the same. You can substitute the 430 crank. The connecting rods are the same. Of course the pistons are not.
Also notice that your engine mount pads are cast into the front of the block. In 1959, there was a running change whereas the blocks were cast for either front mount or center mount (I believe the BIRD retained the front mount into 1960). These will have casting nos. that are more familiar to most (B9AE). There is a post somewheres on this board that will show and describe the differences.
It is nice to have an extra MEL assembly as service parts are getting hard to come by.
Are you wanting to keep your BIRD numbers correct?
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