You're right, this is a car you are going to drive every day there isn't much you should remove or replace to lighten it. Tearing out most of the interior, a/c, heater, inner fenders, stereo, speakers, ect. Would only take off about 200 pounds, .2 of your et. Not the right route to take IMO.
The Performer is isn't much better that an stock 4 barrel intake, the Performer RPM is designed for performance and will give you more all around power. http://www.73-87.com/chp/dyno3.htm
look at test 2 and 3, the difference between the test are they went from a Performer to a Performer RPM and switched to a Holley(which probably only added a few horse power, the majority of the increase is because of the intake.