Not content with retiring to his Spanish villa, picking up a peerage and sniffing around the Leader of the Lords job, Peter Hain is trying to stitch up his seat for his chosen successor. Next week he plans to wangle the selection in Neath for Mabel McKeown, daughter of £75 million comedian Tracy Ullman. As Guido revealed in yesterday’s Sun, Hain’s former agent Howard Davies is running McKeown’s campaign to parachute in his favourite candidate. Opponents claim she has no knowledge of Neath and no local experience since she was born in LA. Carpet-bagging former Harriet Harman aide Mabel has already lost out before for a local council seat and when she stood for the London Assembly. Christina Rees is the Unite union backed rival on the all women shortlist whom Ullman’s daughter is telling to “Move over Darling”…