American industrial heiress Nancy Shevell and Beatles legend Sir Paul McCartney plan to wed Sunday at The Old Marylebone Town Hall. The soon-to-be married couple arrived at London's registers office Saturday to organize some final details before heading to McCartney's St John's Wood home in north London.  

Shevell and McCartney have been together for four years and were engaged last May.

This is the third marriage for Sir Paul, 69, who married his first wife, the late Linda Eastman, at The Marylebone Town Hall as well in 1969.

Paul's found happiness at last and can't wait to marry Nancy. The rest of the family love her and are thrilled she's made their dad so happy, a source told British tabloid, The Sun. McCartney's children, including Stella, 40, are said to have given their blessing to Nancy.

A small wedding reception is expected at Sir Paul's house nearby in St John's Wood.  

It will be very small, just family, a source told The Daily Mail. McCartney's five children are expected to attend.

Miss Shevell, 51, will be wearing a dress designed by Macca's daughter Stella.

It is rumored that the newlyweds also have plans for a second ceremony next week in the Hamptons area of Long Island, New York, where they fell in love in 2007.