The type of fingerboard inlays have been changed two times for the 540R. First year's models have smaller pearl dots. This changed somewhere around 1989 to the more standard sized pearl dots. On 1990-1992 models these dots were combined with a 'Custom Made' inlay on the 21st fret. Unlike what is stated, the 540R models with this inlay were not actually 'custom made' specially ordered personalized guitar models, all standard production models featured them. Other models with this kind of inlay are the 540S and 540R-LTD.
540R BB (1987 model, with 3 toggle switches for pickup selection)