Yeah, just 289 would have done... but what if it had been a 260? Or was it a RuddSpeed Ace... hard to tell from a 260/289!
Only joshing with you, Mark... I`ve not really heard the term 'slabside' used to denote kit/replicas specifically(as there are so few 260/289 replicas...) just anything that`s not a 427 shaped Cobra. Horrible term. Maybe we should call all 427`s 'Fatarses'... see how they like it?!
In future, keep a camera or your phone at the ready at all times in case something interesting happens past, which getting nearer to revival time is likely to be often!