I'm not sure about that I'm afraid. I always thought it was the Grand, until I saw the film a second time.
But over 20 years ago, on a family day out to Brighton, I had an urge to find the alley where Jimmy had more than a snog with Steph. I just went where I reckoned it'd be. I knew they went past a cinema in the film, so I found that and went from there. To my amazement, I found it. at the end was 'THE' door, scrawled with graffiti and fan messages. I took a few pics and was so pleased that I'd found the right place. I wonder if it's still there now?