Yep, with those bars probably need + 8"-10" cables. The stock clutch cable is about 51" (outer sheath plus that elbow thing). Could take a cable, or long piece of fuel line, and kinda mock-up the routing to the perch. Measure, see how much over 51" you get. Throttle cable will need same amount of extension.
I like that Le Pera seat. Would you mind measuring and posting the seat bottom measurements? Widest width and nose to fender length? My seat is an old E&S, 8" wide. I've gotten wider, no cure for that, and been looking for a 9"-10" width in a style like ours.