1) Do not remove the bumpstops. They are part of what keeps the shock from bottoming out.

2) If these springs have been installed on your OEM shocks, expect the shocks to wear out in about 6 months from now.

When they are worn out, replace them with a stiffer shock like the KYB AGX -- or the KYB GR2 if you're on a tight budget. And yes, you'll need to get the car re-aligned. That's why it's a much better idea to install aftermarket springs and shocks together at one time.