Complex sentence: Stewart also co-hosted with Jim Perry for a week around late 1983, when then-hostess Lee Menning was on maternity leave and participated in several Instant Bargains during the course of his tenure on "Sale".
Split into simpler sentences: Stewart also co-hosted with Jim Perry for a week around late 1983, when then-hostess Lee Menning was on maternity leave. He participated in several "Instant Bargains" during the course of his tenure on "Sale".