Stokie,
I have a US spec 350/4 and a UK 400/4, the bars are the same diameter but the clamping is different - 2 separate clamps on knurled areas on the 400 but a single clamp with idiot lights on the 350. Can't remember if the bars are knurled on the 350 but imagine they would be.
The riding position on the 350 is far more relaxed for an old bugger like me but it's also helped with the footrests being further forward than the 400. Cables and upper brake pipe flexy might need modding as Bryan says but the 350 bits should fit.
Ian