Tannas

2005 Mustang has Instrument panel issues, first my gas gauge stopped working about a year ago, now within past 3 months my check engine light comes on then goes out, repeatedly. My speedometer will stop working after I have been driving about 30-45 minutes, but only sometimes, it may go a month without having an episode, BUT last night I noticed at the time my speedometer was quitting, the temperature was steadily going up, but when I pulled off the road and raised the hood, my car was not overheating. Could all this be caused by the PCM (instrument cluster) possibly?? will someone kindly point out where this module is located on the 2005 4.0L V6 Mustang? Thank-u very much!