Am I able to shorten/cut the steel wires and perlon hanging wires myself?
You are not able to shorten the steel cable hanging wires yourself. You would, in principle, be able to shorten the perlon hanging wires, but if unsuitable scissors are used, the wire can become distorted, meaning it is difficult or impossible to insert this through the hanging hooks. We recommend that you roll up the surplus hanging wire and place this behind the picture. If you do decide to shorten the wire yourself, use a high-quality, sharp, utility knife.