Use serrated blades or putty knives to gently remove foam insulation, and for tougher areas, use a power drill or grinder.
Vermiculite insulation is a pebble-like, pour-in product that is light-brown, gray, or gold, often with shiny flakes or small accordion-like pieces.
Use R-19 or R-21 kraft-faced fiberglass insulation for 2x6 walls to ensure it fits snugly without being too loose or too tightly packed.