Eagle1 On Radar Picket Submarines
Eagle1 has a good piece on the history of radar picket ships; there's quite a bit about the submarine version towards the bottom of his post. One of his resources is this excellent article from an old Undersea Warfare magazine. An example of one of the post-war radar picket conversion submarines is USS Tigrone (SSR 419):
You can find more on the Tigrone here.