I sold that car as a kit to Chris Radbill of Radbill Automotive and Restoration. I saw it once after it was built and it seemed to be very well done. IIRC it had a 912 motor at that time, although the ad says it has a new CB 1915, so not sure what happened there? May be my bad memory.
I have used Chris for warranty work, and he has built a few our our cars from the Deluxe Body Package (kit) stage. I have several clients that use Chris for their regular maintenance as well. I haven't heard any complaints.
04/05 was a changeover year for several items, including turn signal unit and wiring harness, so I'm not sure if this one has the old style or new style.
If you are in PA then having it already PA registered and inspected is a big plus. PA has become one of the tougher states to register component vehicles, with a lot of "hoops" to jump through in order to do so.
If you are not in PA, be sure to find out how it is titled (year/make) to make sure it will be a smooth title transfer into your home state.