Complex sentence: Producer Bob Guccione, the magazine's founder, intended to produce an explicit adult film within a feature film narrative, which made use of high production values, casting Penthouse Pets as extras in unsimulated sexual scenes filmed in post-production by Guccione and Giancarlo Lui.
Split into simpler sentences: Producer Bob Guccione, the magazine's founder, intended to produce an explicit adult film within a feature film narrative, which had high production values. He intended to cast Penthouse Pets as extras in unsimulated sexual scenes filmed during post-production by Guccione and Giancarlo Lui.