The frames are completely different animals, as are the engines. The SOHC engine will fit, yes, but it would take an evil genius with good welding and fabrication skills and damn near an engineering degree to do it. Or, a few of the guys on here who seem to have a knack for doing stuff that shouldn't be possible could do it, but it would still take a lot of calculating for clearances and welding. I'd either stick with the DOHC, or buy a SOHC bike.