Where is a good line to hard tap for 12v for inverter besides the cigarette lighter?

 

if you can, just go directly to the battery, if not use one of these:

12volts wht/red - wht/pur + ignition harness
Notes: The ignition harness wires change color at a plug. The above listed colors show both sides of the plug.

Accessory red/yel - red + ignition harness
Notes: The ignition harness wires change color at a plug. The above listed colors show both sides of the plug.