Ha ha! The Embassy gig was when I first encountered 'punky Steve'. Tattoos down the back of his legs. A bit of a dangerous character apparently. Off his tits that night so it seemed. Like you I'd seen masses of gigs gigs before 1977. Small world.
The Jam gig at the Embassy was some gig. A fight broke out in the audience and as the coppers turned up and started dragging people out, the band started playing There's a Riot Going On. Great gig.