Did Our Paul Die In 1968?

In my April 22, 2013 post I speculated on the true identity of our Paul by using three clues I found in doing research:  1.) The Tokyo interview of June 30, 1966 where Paul said he was twelve when he went to a 1957 Bill Haley concert in England; 2.) a KRLA Beat (the fan magazine produced from October 7, 1964 to May 4, 1968 by Los Angeles radio station KRLA) article called "Paul Exposed" that described Paul's fictional songwriter Bernard Webb.  Paul used the name Bernard Webb as the writer of his 1966 song, "Woman" and he also gave a background for Bernard Webb that, I believe, was really autobiographical of our Paul's life; 3.) The song "Substitute" by The Who that hinted that Paul's real last name was BLACK.

I used the Haley concert, Leeds as hometown and last name Black clues to search in the British birth, marriage, death database, FreeBMD and found a birth of a David M. Black that matched those three details.

In the past 2+ years, I've done more digging and found a death listing in FreeBMD that is chilling and closer to newer information I have found.

1.)  I still think our Paul's real last name is Black.  You can add The Rolling Stones' "Paint It Black" with its repeated references to black and its backmasking [see my post of June 18, 2013] to The Who's song.  Also, read my last post.  The new, new Beatles played with the idea of our Paul as Superman.  Now take a look at the Superman cartoon found in the Magical Mystery Tour booklet and notice the "B" on his chest.  It could  stand for Beatles, but I'm guessing it stands for BLACK.
2.)  I think the Leeds-as-Paul's-hometown clue is valid.  The KRLA Beat article said Webb [Paul] is (or had been) a college student.  Our Paul replaced the real Paul in November, 1963 at ~the age of 19 or 20.  If he had been a college student for a year or two prior to joining The Beatles, where did he go to school?  In a May 2, 1966 interview Paul gave to BBC Radio's Saturday Club, Paul was talking about attending theatre productions:
     "When I was in Liverpool, I used to once or twice just go to Liverpool Playhouse, which is a repertory there."  (3:34-3:41 in interview)  Note that he didn't phrase the answer in a say that implied he grew up in Liverpool.  He then said:
     "But I went, when I came out to London, I went to something which wasn't like those plays that they did in repertory.  So, I don't know, you just come down and see some great actors . . . ."  (3:53-4:04.)  You have to read between the lines of what he was saying.  He didn't say, "After I became a famous Beatle, we were often in London and I started going to plays with Jane Asher."  He was hinting that, pre-Beatles, he had come down to London.  If he became a Beatle when he was ~20 years old and had been a college student before that, he likely attended a college in London.
3.)  I've talked on another discussion board about my recollection as an original (1964-1966) Beatles fan that Paul's real first name was JOHN and that he used the name PAUL to not confuse fans with two Johns. There also is the curious statement in Hunter Davies' 1968 authorized biography of The Beatles that Paul "was born John Paul McCartney . . . ."  The real Paul's real first name was JAMES.
4.)  Our Paul's mother might have died when he was ~3 years old according to a 1980 Playboy interview question from David Sheff to our John:
     LENNON:  Whereas Paul had lost his mother but never lost his father.
     PLAYBOY:  Yes, he lost his mother very young.  At about three.
     LENNON:  Yeah . . .  . . ..
Add to this another Playboy interview published in February, 1965 when Paul was asked about his family:
     PAUL:  I've got one brother, and a father who used to be a cotton salesman down in New Orleans, you know.  That's probably why I look a bit tanned . . .  But seriously folks . . ..  He occasionally had trouble paying the bills, but it was never, you know, never 'Go out and pick blackberries, son; we're a bit short this week.'"
Notice that Paul as early as 1964 hinted that the cotton salesman father James was not  his father.  And he did not mention his mother as being alive when he was a child.  Also remember the real  Paul McCartney's mother died in 1956 when the real Paul was fourteen. 

SO . . . with new information in hand, I searched the FreeBMD files again with these parameters:
     1.)  Our Paul's last name was BLACK.
     2.)  His first name was JOHN.
     3.)  His hometown was LEEDS.
     4,)  His mother died when he was ~3 YEARS' OLD.

I came up with a series of listings--marriage, birth, death, death--that, with two exceptions, come as close to the true identity of our Paul as I've been able to find.

First, the two exceptions.  1.) The June 30, 1966 interview that would have put his birth year at 1944 (or 1945.)  2.) The listing I found that might be Paul's mother has her giving birth  when she is ~47 years' old (although that is not out of the range of possibilities.)

Here are the listings:
     1.)  PHILIP BLACK and MAY HARRIS        Marriage in LEEDS, listed June,
                                                                                         1940.

     2.)  JOHN BLACK (with the mother's         Birth in Bradford (17 Miles SW of
             maiden name, HARRIS)                         Leeds), listed March. 1942.

     3.)  MAY BLACK, 52                                            Death in Howden[shire], a town in
                                                                                          the East Riding of Yorkshire (42
                                                                                          Miles E of Leeds), listed
                                                                                          December, 1946.

     4.) JOHN J. BLACK, 25                                       Death in St. Marylebone district
                                                                                          of London.  (Paul's 7 Cavendish
                                                                                          Av. house is in this district),
                                                                                          listed March, 1968.

                                            DID OUR PAUL DIE IN 1968?

NOTE:  I made an attempt to find a probate record for John J. Black in 1968 and I found a website by the UK government that is new (in Beta):
                                           probatesearchservice.gov.uk
I looked for Beatle-related probate records and found listings for real Paul's mother and father, Brian Epstein, George Harrison . . . but nothing for John J. Black.