Rattle at 14-1500 rpm's

Lately, I have been getting a rattle at 14-1500 rpm range everytime I drive. Suddenly though today, I got the rattle from idel to about 3k through third gear, in fourth it doesn’t happen. But always at about 1500 rpms. It sounds to me from the drivers seat that it is comming from underneath the car right under me or around that area. My dad tried to hear it from the engine bay but couldn’t. I am thinking that it may be a heat shield, but am not sure and am not sure what I will need to take it off the car. Thanks
Peace’
Jimmy
And yes, I did search and did see this thread…http://www.g2ic.com/forums/showthread.php?s=&threadid=11214&highlight=rattle and this one…http://www.g2ic.com/forums/showthread.php?s=&threadid=9288&highlight=rattle I just want to be sure before I go removing anything and so my dad will let me.

Before you start ripping out the exhuast heat shields, I would first take a high pressure wash and try to wash out whatever that is stuck in the first. Usually theres alot of rock and debris that get caught up in there over the years. The heat shields are located underneath the car runnin along with the exhuast. All you would need is a jackk some jackstands and a metric socket set. I believe the bolts are 10mm if i remember rite.