Supergroups are, by nature, logistical nightmares. Those incorporating living legends are even less sustainable. Which is why you should head to the Malonga Casquelourd Center (428 Alice St., Oakland) this weekend, when composer, arranger, producer extraordinaire Van Dyke Parks’ ornate, panoramic Americana — as heard in his lyrics for Brian Wilson’s fabled Smile project, and in his sweeping arrangements for Joanna Newsom’s Ys — will collide with Oakland singer-songwriter Matt Montgomery’s Sir Paul-indebted pop delivery and the genre-busting approach of the Bay Area’s own Awesöme Orchestra. Sunday’s show celebrates the release of Petty Troubles: an album of Montgomery-penned songs, recorded live with an ensemble of 28 local musicians over a single day, and will be accompanied by a documentary film chronicling the zippy creative process. Few singer-songwriters, let alone a modest, low-key figure like Montgomery, are ever lucky enough to assemble such a dream-team onstage, making this improbable, one-off collaboration all the more exciting.