When John Lithgow, who plays Cliffhanger's dastardly British villain, first met Sylvester Stallone, he extended an actor's compliment, praising him for being so willing to stretch. ''Yeah, you know what you get for stretching,'' Stallone growled. ''Nothing but stretch marks.'' Here, the Italian Stallion chews over his oeuvre, and-was there any doubt?-proves he's willing to take his punches. * THE LORDS OF FLATBUSH (1974) Newcomers Stallone, Henry Winkler, and Perry King play innocent '50s gang members. ''I have very fond memories of it. The acting was very naturalistic because we were really winging it, and I didn't know any 'cinema tricks.''' * ROCKY (1976) He wrote the screenplay, insisted on starring, and became a bicentennial success story when it won the Best Picture Oscar. ''Rocky was probably the purest of all my performances and the most insightful. It was far better received than I ever thought it would be. Being naive, I thought I was basically doing a film to while away the summer. ''The most important scene was going to be cut for lack of money (Rocky's prefight crisis of confidence, when he confides to Talia Shire's Adrian, ''I can't beat him. Who'm I kidding? All I want to do is go the distance.''). They were literally packing up the equipment. But I stood my ground. So they said, 'Okay, you only get one take, no angles, no coverage.' The next day, they said, 'You know, Sly, that's the most important scene in the movie.' I said, 'Thank you.''' * PARADISE ALLEY (1978) This period wrestling melodrama marked Stallone's directorial debut. ''Also one of my better performances. The character I play is kind of distasteful, but I never worked more on trying to catch the Damon Runyonesque speech pattern. I loved directing. It just seemed to go naturally with my hyperactivity. Again-I use the word a lot-there was that naivete. But that's what was special about the early years before I became the old pro.'' u F.I.S.T. (1978) Director Norman Jewison's fictionalized version of Jimmy Hoffa's career was more Hoffa than Danny DeVito's Hoffa. ''A real eye-opener. That was the beginning of me understanding that I'd been typecast as Rocky. F.I.S.T. and Nighthawks people bring up the most as my most forgotten films.'' * ROCKY II (1979) As much a rematch as a sequel, this time with Stallone writing and directing. ''Once you've tasted success, to follow that up is almost as interesting. Of the Rockys, it was kind of overlooked, but I think it was one of the better written ones. Everyone had their characters so down, all I had to do was say, 'Action.''' u VICTORY (1981) POWs in a German camp turn into a bunch of soccer nuts. ''Working with John Huston was the enticement. At time, he was not feeling very well. I envisioned it to be like a Stalag 17, a depressive prisoner-of- war camp. What came out was like a holiday camp. It was just a little too benign.'' * NIGHTHAWKS (1981) Stallone and Billy Dee Williams follow the trail of a terrorist in New York. ''It was a little bit ahead of its time in that I was dealing with urban terrorism. Now, with the World Trade Center, it's happening. At the time, people couldn't relate to it, and the studio (Universal) didn't believe in it. Rutger Hauer's performance held it together-he was an excellent villain.'' u FIRST BLOOD (1982) Out of this melodrama about a vet who goes berserk in the Pacific Northwest came a new pop icon: Rambo. ''I thought it was going to be the end of my career. The book was interesting, but I thought he was such a psychopath, it would never fly. Every day I worried. When we saw the first cut it was devastatingly bad. My agent said, 'Maybe we can buy it back.' But we cut it to about 90 minutes, and the result was, I think, one of the better vehicles I've ever been in.'' * ROCKY III (1982) In search of another worthy opponent, Stallone drafted Mr. T. ''To me, it's the smoothest of them all. Again I went back into my life. Now Rocky'd become very successful, and he'd lost his eye of the tiger, his edge. He'd developed fear of trying to do things new and unknown. That movie was kind of a psychodrama for me.''



