I would also say that you have at least one faulty Wheel Speed Sensor although I'd like gumdo to elaborate on
Originally Posted by gumdo
Motor Kit $400-500. The relay $14.99, the Valve Kit $799.00, and the fluid
I'm unfamiliar with these parts.
I'd check for broken or disconnected vacuum lines to troubleshoot the high idle.
To test the fuel gauge, disconnect the 4 pin harness to the tank. Turn ignition on. Gauge read full? If so, the sending unit is bad. If not, the gauge in the cluster is at fault.
You can temporarily disconnect the alarm to verify if this is your current drain. You may need to reconnect the starter wire depending on the alarm.