A record of lawful admission for permanent residence may, in the discretion of the Attorney General and under such regulations as he may prescribe, be made in the case of any alien, as of the date of the approval of his application or, if entry occurred prior to July 1, 1924, as of the date of such entry, if no such record is otherwise available and such alien shall satisfy the Attorney General that he is not inadmissible under section 1182(a)(3)(E) of this title or under section 1182(a) of this title insofar as it relates to criminals, procurers and other immoral persons, subversives, violators of the narcotic laws or smugglers of aliens, and he establishes that he—