I dont know where the write-up is but all you have to do is get a cheap piezo buzzer from radio shack compatible with 12vdc and wire the positive lead of the buzzer to the positive wire of the marker light and the negative lead to the ground door jamb button. Now, only when the lights are on and you open the door the buzzer will sound.

Hope this helps,
Buddy

'98 Tacoma TRD ext.cab 2.7 5spd 6inFabtech sus w/ 33x12.5.15 TrxusSTS on 15x10 DC-1 (Black)

'90 4Runner 3.0auto stock as of now