Bluetooth Arduino OBD2 Sensor

Hey guys, I am trying to find a way to have LEDs that change color with the RPM in my car. I have been doing research, and I've seen a lot of people do it with a corded OBD2 sensor, but I would like to do it with a bluetooth OBD2, making it a lot more sleek. Have any of you done this?

I would think that I could get a bluetooth shield for my arduino uno (or get an arduino bt) and connect with the ELM327 bluetooth miniOBD2 via bluetooth. (my obd2 sensor has R232 to bluetooth protocol btw). But, I don't know how to initialize that communication. After i initialize that communication? How to I go about reading specific data from it?

Open-ended question, looking for an open-ended answer. Thanks!