[Mike Taylor 3601]

You can put adapt for 2 pc. seal like you've seen, but oil pan is different where it meets up with rear cap, but I have seen blocks that have rear cap for 2 pc. seal and block is machined for adapter that bolts to block and holds seal,it was bowtie block.
Don't know if came that way or was modified,if had to modify to that configuration would be cheaper to buy pan.
I think you could modify pan for 2 pc. to fit 1pc.by changing that section in pan.
Mike Taylor3601