Cut out the corresponding template-sized rectangle and use this to measure the cut-out size drawing your cut lines directly onto the wall of the container
Using an oscillating saw or Dremel tool with a plastic blade cut along the lines carefully and remove the cut-out piece.
Use a Dremel tool with a sanding edge to smooth the cut edges until all four edges of the portal inner lip fit snugly into the created pass through.
Interlock two corners of the Portal system and place them in position.
Using the predrill guides and a very small drill bit predrill the first corner and secure with a hand screwdriver using the provided screws. *Screwing it in by hand will prevent stripping of the material of the portal.
Repeat this process for the remaining corners
Once all corners are secure then predrill the remainder of the securing holes and secure using the remaining screws
