Awhile ago (don't ask me how long ago because time slips away) someone posted how to install seat belt bolts through a carpet without damaging it. I've been searching but can't find it. Please refresh my memory.
It might have been to use a hot soldering iron or a heated old pointed punch. It melts a hole thru the carpet & fibers so they don't unravel, leaves a clean round hole with a 'bound' edge.
also heard a step drill will drill thru carpet without damage. also heat up a piece of correct sized pipe. it will melt thru the carpet and seal off fibers