FYI,
I have just replaced my leaking Dukes boost pump with the new Weldon one. It was pretty easy swap. I did it myself and my mechanic supervised and sign it off.
The original Dukes was 1499-00-19A on my 1977 M20J and the direct swap is Weldon 18020-A. First I have ordered the Weldon A8186-A as it is listed under Mooney within my serial number range but it was wrong one. I paid $ 793 at Aircraft Spruce which is pretty good deal compare to the new or even overhauled Dukes.
I have read som