plugs are a little white

[qwikhuh]

I am pretty new to the mustang world. I got a 91 GT back in Jan. I changed the plugs when I got it and again about a month ago. It has BBK equal length shorties, BBK h pipe, flowmasters, underdrive pulleys, MSD coil, and a BBK fenderwell mount intake, precision 3.73's, Ram clutch, Pro 5.0 shifter, Accel cap and rotor, Moroso Blue Max wires, fomoco alum. driveshaft, and a few other goodies. I just got an electric fan and fomoco upper control arms. Got the car for 2600 bucks, so I can't complain. Here is the question. I changed the plugs and they are a little too white for my liking. I checked the fuel pressure with vac. 37 w/o vac. 44. I don't really know where to go from here. I have always had vehicles that I just drove, and not monitered. Any help would be appreciated. Also the car doesn't seem to run quite right when you get on it around 2k rpm. From about 2K-3K is seems a little weak. I think it may need a new harmonic balancer. At the same time it runs a little weak it also vibrates through the shifter w/clutch pushed in and in neutral. After that (3K) it runs like a raped ape. The check engine light isn't on either. Thanks in advance for any help.