I'm running a shorty which is actually a pinch too light so I've added some lead weight in front of the pack to get my car to the min weight limit of 1380g for my local club.
Some brands of electronics weigh less than others, I'm also running an MRT transponder which is a few grams less than MYLaps. I also run titanium screws on all the upper parts of the chassis to help lower the center of gravity.