OK, so I drove to work and it seems better. I did not have any low RPM drops at lights/stop signs. When I pulled into the lot at work and stopped to back into my spot, it dropped but that may have been from a quick stop, wheels at full lock and shifting into reverse. I am still getting, for lack of a better description, a slight "stutter" while at idle. This is very, very slight and might be normal?
I am thinking that I might have had/have a really small leak at the manifold. So, I will probably go around and retorque all of the bolts to factory specs. Does anyone know what the factory specs are for the intake/exhaust manifold?
Also, after doing some reading, I am thinking that tin foil shield I took out was a "debris shield." Is that correct? If so, I will not worry about putting anything back in. Thanks everyone for all the help.