The measure of the curvature of the top of the fretboard from edge to edge is often incorrectly referred to as the "neck radius". Actually, the correct terminology would be either "fretboard" or "fingerboard radius" and the actual neck shape and size should be called "neck profile". The fretboard radius can be found by first drawing a circle with a corresponding radius, (the "radius" is the distance from the center of a circle to its outer edge), and then cutting out a portion of that circle corresponding to the width of the fretboard.
A guitar's scale length is calculated by measuring the distance from the front edge of the nut to the center of the 12th fret, then doubling that measurement. For good intonation, the guitar's saddle will be placed so a little extra string length is added. This extra length is called compensation, and it means the actual string length is longer than its scale measurement. Compensation varies for different strings, and that's why your saddle is placed at an angle. Example a 24 3/4" scale length will be closer to 24 7/8" at the center of the guitar saddle.
From 1974 through 1981 Hamer USA employed two separate serial numbering systems, one for custom instruments and one for production models: Custom Instruments: These instruments are easily recognized by the use of a four digit number stamped into the wood on the back of the peghead. The numbers ran from #0000 through #0680. All of the early Hamer USA Standards and 12-String basses as well as a number of prototype instruments were included in this serial numbering system.
The following file will help you date your PRS Guitar, PRS Bass, PRS Amp or PRS Cabinets. PRS serial numbers are pretty easy to decode. One confusing thing is a 1985 guitar starts with the same number as a 1995 guitar, 1986 guitars starts with the same number as a 1996 guitar, 1987 guitars start with the same number as a 1997 guitar etc. All you have to remember is, guitars built in 1985 would have a very low number, while guitars built in 1995 would have really high numbers.