Jidmichat,
What's stumping you may be the fact that, although your frame is stmped "CT-1", what you have there is a "CT-3".
So, the 248-14718-30-00 won't fit, it's for '69-'71 AT1/CT1.
The part number you need is 314-14718-30-00. Lots of the parts are inter-changable between the AT1/CT1 and the AT3/CT3, and actually, between the whole AT1/AT2AT3/CT1/CT2/CT3 family but not the exhaust.
On another note, your exhaust is the same as the US model, fitting the AT2/AT3/CT2/CT3, it just has a longer silencer on it, (is it a factory part?).
Her's the best OEM parts web site, if you search a part and click on it, it'll show you what other bikes it will fit:
http://www.boats.net...ycle/parts.html
By the way, I'm searching for a '69-71 European AT1, non-electric start.