Some will do some crazy stuff. Uncle Tony drilled hundreds of holes in his '67 Dart. Screw that...I want a rigid chassis for better cornering.
Undercoating can be worth between 50-100 lbs. Scraping it off with a needle scaler is the fastest way that I have seen to remove it.
If this is a drag race car, remove the under dash heater or A/C box, rear seat, spare tire and jack.
The K member isn't all that heavy when you consider what it must deal with....the weight of the engine, suspension and steering all rely on the stiffness and rigidity of the K member. I don't trust the aftermarket to build an equally durable K member. Every one that I have seen has drawbacks compared to a stock K member with some minor gussets to the steering box mounts.
