From this site,
http://repairfaq.ece.drexel.edu/REPAIR/F_BC_Repair.html comes this tip,
"Replacement Bulbs for BC760XLT
The Uniden BC760XLT's SCAN, MAN, PRI, and HOLD buttons are illuminated by "grain of wheat" type incandescent bulbs. Gary Saffer reports that the bulbs and buttons are located on a small printed circuit board which sits behind the radio's face plate. Gary unsoldered the burned out bulbs in his radio and replaced them with 12 volt Radio Shack bulbs (#272-1092c). They should last a long time when powered by the 8 VDC supplied by the BC760XLT."
Should work for the 580, which was a non 800 Mhz version of the 760. It also will work for the display light.
Gary