With the Ford factory CD player, you won't lose stations by disconnecting the battery. You'll just lose the time and your bass / treble settings. Easy enough to modify.

1999 Red / Tan SVT #1969 of 2760 Built 4/21/99 K&N, DMD, FMS Wires, ES Insert / Bushings, PF End Links 17" FSVT 5-Spokes Factory Spoiler 35% Tint All Around