I've got the neck from my old fretless, it's an MIJ fender jazz with an N serial # from 1993. JB-355FL is stamped on the neck. I carelessly used rounds on this bass with poor technique for years when young, and at some point wore grooves into the neck and the strings would bite in and buzz in a few choice spots (the A string at the 5th fret, for example). I looked into having a luthier refinish and epoxy it about 10 years ago, it was an option that was too expensive (I'm in NYC and talked to someone at Sadowsky I think) at the time. Long story short - I bought a replacement warmoth neck and got on with my life but was never happy with the neck and that bass was eventually dismantled. I loved this japanese J-neck and have been thinking a lot about it and finally dug it out of my closet with the intent of buying a loaded body and making a project out of it. I'll probably just string it with flats but I think I'd like to sand the fingerboard smooth and get the damage from the rounds cleaned up. I see you can get sand blocks with a radius - but I don't know what the radius of this neck is! My guess is something around 9.5". It is definitely flatter than 7". Can anyone help me with this?