No, on mine, I had two slots there. On the left, where I installed the USB charger was where the cigarette lighter was located. The one to the right that you see is accessory power from the battery. I left one to use a GPS unit or anything else that I might want to plug in.
I believe (don't quote me) on the 97-02's there was an ashtray to the right and only a single cigarette lighter that was mounted in the middle of that panel like you are describing in your setup. I imagine that since you have only one lighter plug, you could drill a new hole left or right of the lighter since you want to keep your lighter too and just splice into the wires feeding your lighter. The fuse for the lighter (on mine) is a 20 amp fuse so there shouldn't be a problem using one of these chargers and the cigarette lighter together...?? I think cigarette lighters only draw about 8-10 amps to heat the lighter and USB chargers draw anywhere from 1.0 amp to I think this 3.0 charger is about 2.4 amps??? So a 20 amp fuse should be fine!