I think Mark's right about the 56 inches total Roscoe, rings a bell here, too. I have an old bashed up pipe and megga in the shed, off a Jawa I think, but to my mind the megga is way too short, I was gunna suggest emailing Antig's Dave Perry for some info, as they still sell new Wessies
Went looking for info on Wessie exhausts on the net and came across a colour, late '70s, Hagon catalouge, it's a pearler, there's a heap of bikes and stuff in it, sent Slides a copy, he was stoked, pm me your email address and I'll send you a copy, I'll send a copy to you , too Mark.
Foss